Access Control: It is determined by the owner of an object. The owner decides who is allowed to access the object and what privileges they have. It includes authentication, authorization and audit. It also includes measures such as physical devices, including biometric scans and metal locks, hidden paths, digital signatures, encryption, social barriers, and monitoring by humans and automated systems.

Address Resolution Protocol (ARP): Used for mapping an IP address to a physical machine address.

Addressable Panel: Usually much more advanced than their conventional counterparts, with a higher degree of programming flexibility and single point detection. Noteable examples include the EST 3, the Faraday MPC-2000 and the Simplex 4100U. Fire-Lite designed the first addressable fire alarm panel in the late 1980s.

Alarm: Gives an audible or visual warning of a problem or condition.

Analogue: Continuously variable numerical values such as voltage, current, etc. (The CCD camera produces analogue video signals.)

Angle of View: The scene angle that a video camera lens can show on the monitor, like Diagonal Angle, Horizontal Angle and Vertical Angle, usually described in degree.

Aperture: The light gathering area of a lens, controlled by the iris.

Aspect Ratio: The ratio of the vertical to the horizontal image size; 4:3 is the PAL standard.

Aspherical Lens: A lens designed with a non spherical shape so that it passes more lights or decreases barrel distortion on wide angle lenses.

Attenuation: A decrease or loss in a signal, usually measured in decibels.

Auto-focus Lens: Automatically adjusts the lens focus from surrounding scene and keeps a moving object in focus.

Automatic Gain Control (AGC): Automatically adjusts the video quality in low light condition.

Automatic Iris (Auto-iris): A diaphragm device in the lens that adjusts to light level changes. The iris diaphragm opens or closes the aperture to control the amount of lights coming through the lens.

Automatic Level Control (ALC): Allows the auto-iris circuitry to either take bright spots more into consideration (peak), bringing out detail in bright areas, or less into consideration (average) bringing out detail in shadows.

Auto Terminating: Automatically select the correct termination depending on whether the video output is connected.

Auto White Balance (AWB): Automatically adjusts a color camera's color to maintain white areas.

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Back Light Compensation (BLC): Electronically compensates for high background lighting to give detail which would normally be silhouetted.

Bandwidth: The capacity of the transmission medium stated in bits per second, as a frequency, or the amount of data that can be transmitted in a fixed amount of time. For digital devices, the bandwidth is usually expressed in bits per second (bps) or bytes per second. For analogue devices, the bandwidth is expressed in cycles per second, or Hertz (Hz).

Baud: A unit of measurement that denotes the number of bits that can be transmitted per second. For example, if a modem is rated at 9600 baud it is capable of transmitting data at a rate of 9600 bits per second.

Bellbox: A device which gives an audible and usually visual notification of an alarm activation.

Binary Digit: The smallest unit of data in a computer; are a basic unit of information storage and communication in digital computing and digital information theory.

Biometrics: Biometric information is detected and compared with the stored information Bits per Second (bps): Is the unit used for measuring line speed, the number of information units transmitted per second.

Blanking: The process whereby the beam in a CRT is cut off during the retrace period.

BNC: One of the most popular of the coaxial connectors. The name BNC sands for Bayonet Neill Concelman. Bayonet describes the coupling mechanism, while Neill and Concelman were the inventors of the N and C connectors. The BNC is essentially a miniature version of the C connector which is a bayonet version of the N connector. BNC connectors are available in both 50 and 75 ohm versions, both versions will mate together. The 50 ohm designs operate up to a frequency of 4GHz. BNC connectors are used in many applications, some of which are flexible networks, instrumentation and computer peripheral interconnections.

Brightness Control: The manual bias control on a cathode ray tube or other display device that controls the average brightness and the contrast of a picture.

British Naval Connector (BNC): A connector widely used in the CCTV industry, usually for coaxial cable. Easy to install and reliable with little video signal loss.

Burglar Alarm: Sensors are connected to a control unit via either a low-voltage hardwire or narrowband RF signal, which is used to interact with a response device. The most common security sensors indicate the opening of a door or window or detect motion via passive infrared (PIR). In new construction systems are predominately hardwired for economy while in retrofits wireless systems may be more economical and certainly quicker to install.

Byte: A unit of data that is eight bits long and is used by most computers to represent a character such as a letter, number or symbol.

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C-Mount: An industry standard for lens mounting. C-Mount is 1-inch diameter with 32 threads per inch. A C-Mount lens needs a C-ring when it is mounted on a CS-Mount camera.

CS-Mount: An industry standard for lens mounting. CS-Mount is 1 inch diameter with 32 threads per inch. A C-Mount lens needs C-ring when it is mounted at a CS-Mount camera. Camera format: Video camera's CCD chips format; 2/3", 1/3", 1/4", etc.

Camera Sensor: Video image sensor. CCD or C-MOS chip.

Carbon Monoxide Detector: is a device that detects the presence of the toxic gas carbon monoxide (CO), a colorless and odorless compound produced by incomplete combustion and lethal at high levels. If a high level of CO is detected, the device sounds an alarm, giving people in the area a chance to ventilate the area or safely leave the building. CO detectors do not serve as smoke detectors and vice versa. However, dual smoke/CO detectors are also sold. Smoke detectors detect the smoke generated by flaming or smoldering fires, whereas CO detectors can alarm people about faulty fuel burning devices. Carbon monoxide is produced from incomplete combustion of fossil fuels. In the home CO can be formed, for example, by open flames, space heaters, blocked chimneys or running a car inside a garage. When an alarm sounds, action must be taken immediately. This may include evacuating the premise if experiencing CO poisoning symptoms (confusion, headaches, nausea, dizziness, vomiting, etc), ventilation of the premises, and contacting professionals to inspect CO emitting sources. If you suspect you have suffered CO poisoning, go outside immediately and call the emergency number. At high levels, breathing CO gas is fatal within minutes.

Category 5 wire: is a twisted pair cable type designed for high signal integrity. Many such cables are unshielded but some are shielded. Category 5 has been superseded by the "Category 5e" specification. This type of cable is often used in structured cabling for computer networks such as Ethernet, and is also used to carry many other signals such as basic voice services, token ring, and ATM

Central Station: A Secure location where signals are monitored 24 hours a day. Area: Segmented section of a security system. is a common term used to refer to a company that provides services to monitor burglar, fire and residential alarm systems. The central-station may also provide watchman and supervisory services. Central-stations use special telephone lines, computers and trained staff to monitor their customer's security systems and call the appropriate authorities in the event an alarm signal is received. Typically, there is a fee for services rendered. Because quality and experience can vary greatly among alarm companies, a prospective customer is well advised do their own research before making a final choice. Not all alarm companies monitor the systems they install and may outsource these services to another company. Some facilities are certified by independent agencies. Underwriters Laboratories (UL) is a leader in inspection and certification of central-stations. UL Standards 827 and 1981 must be adhered to in order to maintain a UL issued Central-Station license. UL conducts annual audits of these licensed facilities to ensure compliance."Licensed" companies typically offer higher levels of service and reliability because they are mandated to follow certain regulations.

Central Processing Unit (CPU): Computer which processes the Control Panel Unit (Alarm).

Charge Coupled Device (CCD): A video image sensor chip.

Closed Circuit Television (CCTV): Is a Television system that sends a signal to one or more monitors rather than broadcasting over a public network, hence closed-circuit. A standard CCTV system will normally include a CCTV camera (for capturing video), transmitters and receivers (to transfer the video from the source to where it is recorded), a recording system (for video playback), and a monitor (for video monitoring). CCTV systems are primarily used for security purposes inside and outside buildings. However, they can also be used for specialist applications such as mobile police use and interrogation.

Coaxial Cable: A cable that can carry a wide range of frequencies with very low signal loss. It consists of a metallic shield with a single wire placed along the center of a shield and isolated from the shield by an insulator.

Color Saturation: The degree of mixture of a color and white. High saturation means little or no white.

Complementary Metal Oxide Semiconductor (CMOS): A video image sensor chip that produces much lower quality picture than CCD chip.

Conventional Panel: Usually have a small number of circuits, each circuit covering a zone within the building. A small map of the building is often placed near the main entrance with the defined zones drawn up, and LEDs indicating whether a particular circuit/zone has been activated. Another common method is to have the different zones listed in a column, with an LED to the left of each zone name. The main drawback with conventional panels is that one cannot tell which device has been activated within a circuit. The fire may be in one small room, but as far as emergency responders can tell, a fire could exist anywhere within a zone.

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Detector: Any device which can be connected to an Alarm system to provide notification of any activation to the control panel.

Digital Communication (Digi-Com): Refers to the field of study concerned with the transmission of digital data. This is in contrast with analog communications. While analog communications use a continuously varying signal, a digital transmission can be broken down into discrete messages. Transmitting data in discrete messages allows for greater signal processing capability. The ability to process a communications signal means that errors caused by random processes can be detected and corrected. Digital signals can also be sampled instead of continuously monitored and multiple signals can be multiplexed together to form one signal. Because of all these advantages, and because recent advances in wideband communication channels and solid-state electronics have allowed scientists to fully realize these advantages, digital communications has grown quickly. Digital communications is quickly edging out analog communication because of the vast demand to transmit computer data and the ability of digital communiations to do so.

Digital Subscriber Line (DSL): A technology for bringing higher-bandwidth information to homes and businesses over ordinary copper telephone lines.

Digital Video Recorder (DVR): Is a device (hardware) that records video in a digital format to a disk drive or other medium. The term includes stand-alone set-top boxes and software for personal computers which enables video capture and playback to and from disk. Some consumer electronic manufacturers have started to offer televisions with DVR hardware and software built in to the television itself. It has also become the main way for CCTV companies to record their surveillance, as it provides far longer recording times than the previously used VCRs.

Direct Current Power (DC Power): Can be derived from an AC adapter or from a battery. DC voltages commonly are 6, 9, 12, 24 or 28. 12VDC is most common in the CCTV industry.

Door Contact: A normally magnetic switch, which detects if a door is closed or open.

Dual Interface Poll (DIP): Switches usually allow you to change the configuration of a circuit board to suit your application.

Dual Technology (DTEC): Where a single device operates on two different types of technology. Must common use is where a PIR and a Microwave detector is combined into one movement detector.

Dummy Sounder: An external sounder that provides a visual deterrent, but doesn't make any noise.

Duress Code: A number chosen by the user that, if used to unset the alarm will act as normal but will also send a personal attack (code 2) signal to the ARC, a simple word or phrase used during normal conversation to alert other personnel that an authorized person is under duress. A duress code requires planning and rehearsal to ensure an appropriate response. This code is changed frequently to minimize compromise.

Dwell Time: The length of time a switcher displays one camera before sequencing to the next.

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Electromagnetic Door Strike: Is a simple locking device that consists of an electromagnet and armature plate. By attaching the electromagnet to the door frame and the armature plate to the door, a current passing through the electromagnet attracts the armature plate holding the door shut. Unlike an electric strike a magnetic lock has no interconnecting parts and is therefore not suitable for high security applications because it is possible to bypass the lock by disrupting the power supply.

Electronic Article protection System (EAS): is a technological method for preventing shoplifting from retail stores or pilferage of books from libraries. Special tags are fixed to merchandise or books. These tags are removed or deactivated by the clerks when the item is properly bought or checked out. At the exits of the store, a detection system sounds an alarm or otherwise alerts the staff when it senses active tags. For high-value goods that are to be manipulated by the patrons, wired alarm clips may also be used; these, being less common and technologically less mysterious, are not covered by this article.

Electronic Light Control (ELC): Compensates for moderate light changes in indoor applications without the use of auto iris lenses. Select this mode when a fixed iris lens or manual iris lens is used.

Electronic Shutter: Compensates for moderate light changes in indoor applications without the use of auto iris lenses.

Emergency Voice Alarm Communications Systems (EVAC): is part of a fire alarm system that uses high reliability speakers to notify the occupants of the need for action in connection with a fire or other emergency. These speakers are special types of fire alarm Notification Appliances. 'Emergency Voice Alarm Communication' systems are employed in large facilities where general undirected evacuation is considered impracticable or undesirable. The Audible Textual signals from the speakers are used to direct the occupant's response during a fire or other emergency. The system may be controlled from one or more locations within the building known as Fire Wardens Stations, or from a single location designated as the building Fire Command Center. Speakers are automatically activated by the fire alarm system in a fire event, and following a pre-alert tone, selected groups of speakers may transmit one or more prerecorded messages directing the occupants to safety. These messages may be repeated in one or more languages. Trained personnel activating and speaking into a dedicated microphone can suppress the replay of automated messages in order to initiate or relay real time voice instructions

Entry/Exit (E/E): the entry/exit point of an Alarm System.

Ethernet: The most widely installed Local Area Network (LAN) technology. Specified in a standard IEEE802.3.10/100 BASE-T, the most commonly installed Ethernet system, provides transmission speed up to 100 megabits per second.

Exit Terminator (ET): A button or other device which when activated triggers the final setting of the Alarm system.

Expander: A Device which expands the capabilities of an alarm system.

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F-Number (F-Stop): Optical or lens speed. Smaller f-number means faster lens.

Facial Recognition Systems: Is a computer application for automatically identifying or verifying a person from a digital image or a video frame from a video source. One of the ways to do this is by comparing selected facial features from the image and a facial database.

False Alarm: Is the phony report of an emergency, causing unnecessary panic and/or bringing resources (such as fire engines) to a place where they are not needed.

Fiber-Optic Cable: One of the video transmission ways, being used for a long distance transmission up to miles. Field: One video frame is composed of two fields; one field consists of the odd numbered lines in the frame and the other field consists of the even numbered lines.

Field Of View (FOV): The width, height or diameter of a scene to be monitored. Usually determined by the focal length of a lens, the sensor format and the distance to the objects.

File Transfer Protocol (FTP): A way to exchange files between computers on the Internet.

Fingerprint Verification: Refers to the automated method of verifying a match between two human fingerprints. Fingerprints are one of many forms of biometrics used to identify an individual and verify their identity.

Fire Alarm: Is an active fire protection system that detects fire or the effects of fire, and as a result provides one or more of the following: notifies the occupants, notifies persons in the surrounding area, summons the fire service, and controls all the fire alarm components in a building. Fire alarm systems can include alarm initiating devices, alarm notification appliances, control units, fire safety control devices, annunciators, power supplies, and wiring.

Fire Alarm Pull Station: Is an active fire protection device, usually wall-mounted, that, when activated, initiates an alarm on a fire alarm system. In its simplest form, the user activates the alarm by pulling the handle down, which completes a circuit and locks the handle in the activated position, and sending an alarm to the fire alarm control panel. Fire alarm pull station are often reset using a key, which allows the handle to go back up to its normal position. Single pull systems are simpler, but run a higher risk of accidental pulls.

Fire Alarm Control Panel (FACP): is a central control device for detecting, reporting and acting on occurrences of fires within a building. There are two types of panels: conventional panels, and analogue addressable panels. In a conventional panel, fire detection devices including, but not limited to smoke detectors, heat detectors and manual call points or manual pull stations are joined up with a number connected to each circuit. When a device on the circuit is activated, the panel recognizes an alarm on that circuit and could be set up to take a number of actions including directly calling the fire department via an alarm transportation system (ATS).An addressable panel is a more modern type of panel, and has greater flexibility than a conventional panel. An addressable panel has a number of loops, where a number of devices are able to be connected, each with its own address. There is no standard protocol as such, and thus a number of proprietary solutions exist. Loop devices have traditionally been able to have 99 or 100 devices connected, but more recent protocols allow many more. This is usually overcome by having multiple loops on one system.

Fire Door (F/D): Is a type of door, or closure used as a passive fire protection item within buildings to prevent the spread of fire. It is usually the only means of allowing people to pass through a fire-resistance rated wall assembly.

Fire Extinguisher: Is an active fire protection device used to extinguish or control small fires, often in emergency situations. Typically, a fire extinguisher consists of a handheld cylindrical pressure vessel containing an agent which can be discharged to extinguish a fire.

Fire Sprinkler: is the part of a fire sprinkler system that discharges water when the effects of a fire have been detected, such as when a predetermined temperature has been reached.

Fire Sprinkler System: is an active fire protection measure, consisting of a water supply, providing adequate pressure and flow rate to a water distribution piping system, onto which fire sprinklers are connected. Although historically only used in factories and large commercial buildings, home and small building systems are now available at a relatively cost-effective price.

Fire Suppression: The fire is extinguished by manual or automatic means, such as a fire extinguisher or a standpipe system or a fire sprinkler system, which automatically releases water, or a gaseous or foam based fire suppression system, to suppress a fire when a release mechanism is activated by heat.

Flash Memory: Or flash RAM (Random Access Memory). A type of constantly powered non-volatile memory that can be erased and reprogrammed in units of memory called blocks.

Fleet Management: Is the management of a company's vehicle fleet. Fleet management includes vehicle tracking, mechanical diagnostics, management of ships and driver behavior tracking.

Focal Length (FL): The distance from the center of a lens (or, the secondary principal point, if it has) to the focal point (sensor). The longer the focal length, the narrower is the angle of view.

Frame: A whole video image; is composed of two interlaced fields. A CCD chip produces 30 frames per second at NTSC system and 25 frames at PAL

Fully Supervised Loop (FSL): The current is constantly flowing through a wire; any disruption in this signal will signify a alarm condition.

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Gamma: Degree of contrast in a video picture between output magnitude and input magnitude.

General Packet Radio Service (GPRS): Is a Mobile Data Service available to users of Global System for Mobile Communications (GSM) and IS-136 mobile phones. GPRS data transfer is typically charged per megabyte of transferred data, while data communication via traditional circuit switching is billed per minute of connection time, independent of whether the user has actually transferred data or has been in an idle state. GPRS can be used for services such as Wireless Application Protocol (WAP) access, Short Message Service (SMS), Multimedia Messaging Service (MMS), and for Internet communication services such as email and World Wide Web access.

Genlock: A device that adjusts the frequency of internal sync to an external data.

Ghost: A shadowy or weak image in the received picture, offset to either the right or to the left of the primary image. Gigabyte (GB): When referring to RAM sizes and file sizes, it traditionally has a binary definition, of 1024 bytes. For other uses, it means exactly 1000 bytes.

Glass Break Detector (GBD): This sensor triggers an alarm signal when it hears the sound of breaking glass

Global Positioning System (GPS): Is the only fully functional Global Navigation Satellite System (GNSS). Utilizing a constellation of at least 24 medium Earth orbit satellites that transmit precise microwave signals, the system enables a GPS receiver to determine its location, speed, direction, and time.

Global System for Mobile Communications (GSM): Is the most popular standard for mobile phones in the world. Its promoter, the GSM Association, estimates that 82% of the global mobile market uses the standard. GSM is used by over 2 billion people across more than 212 countries and territories. Its ubiquity makes international roaming very common between mobile phone operators, enabling subscribers to use their phones in many parts of the world. GSM differs from its predecessors in that both signaling and speech channels are digital call quality, and so is considered a second generation (2G) mobile phone system. This has also meant that data communications were built into the system using the 3rd Generation Partnership Project (3GPP).

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Heat Detector: Is a device that detects heat and can be either electrical or mechanical in operation. The most common types are the thermocouple and the electro-pneumatic, both respond to changes in ambient temperature. Typically, if the ambient temperature rises above a predetermined threshold, then an alarm signal is triggered.

Hertz (HZ): Frequency in Cycles per second.

Hidden Camera: is a still or video camera used to film people without their knowledge. The camera is "hidden" because it is either not visible to the subject being filmed, or is disguised as another object. Hidden cameras have become popular for household surveillance, and can be built into common household objects such as smoke detectors, clock radios, motion detectors, ball caps, plants, and cellphones. Hidden cameras may also be used commercially or industrially as security cameras

Hub: As a network product, a hub may include a group of modem cards for dial-in users, a gateway card for connections to a Local Area Network (LAN), and a connection to a line.

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Impedance: Electrical characteristic of a system or component, expressed in ohms. CCTV industry has standardized 75-ohm impedance.

Infrared (IR): Light Invisible light beyond the 750 nano-meters (red end of the visible lights).

Ingress Protection (IP): Normally in the form of a rating whereby the higher the number the more difficult for a foreign substance/object to ingress into the equipment.

Input/Outputs (I.O.'s): Refers to the communication between an information processing system (such as a computer), and the outside world - possibly a human, or another information processing system. Inputs are the signals or data received by the system, and outputs are the signals or data sent from it. The term can also be used as part of an action; to "perform I/O" is to perform an input or output operation. I/O devices are used by a person (or other system) to communicate with a computer.

Integrated Service Digital Network (ISDN): A set of standard for digital transmission over ordinary telephone copper wire.

Internal sync mode (INT): That sets to internal 2:1 interlace.

Internet protocol (IP): Is a data-oriented protocol used for communicating data across a packet switched inter-network. Iris: An adjustable opto-mechanical aperture built into a camera that controls the amount of lights coming through the lens.

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Joint Photographic Experts Group (JPEG): A graphic image file or an image compression algorithm.

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Key Fob: Used in many types of building such as houses, apartments and condominiums for access to common areas (ie. lobby doors, storage areas, fitness room, pool). They can be programmed to allow access only to those areas in which the tenant or owner is permitted to access, or only within certain time frames.

Key holder: A nominated person, who is deemed able to operate the security system, has keys as required and lives within 1 hour traveling time.

Kilobyte (Kb, Kbps): A measure of bandwidth.

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Lens Mount: The area where a lens is mounted. There are two types; C- or CS-Mount.

Lens Speed: Optical speed, expressed by f-number. Smaller f-number means faster lens.

Line Lock (LL): Mode LUX Lumens per Square Meter; unit of illumination amount.

Linux: An UNIX-like operating system. Very efficient and fast-performing system

Light Emitting Diode (LED): Is a semiconductor diode that emits incoherent narrow-spectrum light when electrically biased in the forward direction of the p-n junction. This effect is a form of electroluminescence. An LED is usually a small area source, often with extra optics added to the chip that shapes its radiation pattern. The color of the emitted light depends on the composition and condition of the semi conducting material used, and can be infrared, visible, or near-ultraviolet. An LED can be used as a regular household light source

Local Area Network (LAN): A group of computers and associated devices that share a common communications line.

Loop: Panels usually have a number of loops within the range of two to 20 loops. At the present time, four or six loop panels are the most common. Each loop can have a number of devices connected to it. Each device has its own address, and so the panel knows the state of each individual device connected to it.

Lux (lx): is the SI unit of illuminance and luminous emittance. It is used in photometry as a measure of the intensity of light, with wavelengths weighted according to the luminosity function, a standardized model of human brightness perception.

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Master Code: The operators code for the system that has additional privileges such as being able to delete other user codes.

Magnetic Reed Switch (MRS): It is found in Door Contacts and PA Buttons. Medical Alert: is an electronic device worn on a bracelet or necklace as part of a medical alert system. When pressed, it sends a wireless signal to a home console which dials alarm monitoring staff and alerts them of an emergency condition. Depending on the severity of the situation, alarm monitoring staff will summon friends, family, or emergency services.

Megabyte (Mb, Mbps): A measure of bandwidth.

Metal-Oxide Semiconductor (MOS): One of video image chips like CCD, but it produces lower quality video.

Monitored: The basic idea of alarm monitoring is simply to inform a key holder and/or local police, that the alarm system has been activated.

Monochrome Signal: Black and White signal.

Motion Detector: Contains a motion sensor that transforms the detection of motion into an electric signal. This can be achieved by measuring optical or acoustical changes in the field of view. A motion detector may be connected to a burglar alarm that is used to alert the home owner or security service after it detects motion.

Motorized Lens: A camera lens equipped with small electric motor that enables focusing lens, opening or closing the iris diaphragm, or changing the focal length.

Moving Picture Experts Group (MPEG): A standard for a digital video & audio compression.

Multiplexer (MUX): Combines two or more video/audio signals into one channel. Usually accepts 10 or 16 video inputs and displays them in various formats.

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National Television System Committee (NTSC): Formulates standards for American color television system. NTSC system has 525 horizontal scan lines and 30 frames per second.

Noise: Undesired signals that corrupt the original video signals and may reduce the image quality.

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There are no definitions under the letter "O" at this time.

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Pan: Rotating or scanning a camera side ways to view an area in a horizontal direction.

Pan and Tilt: A Camera mounting device that allows movement in both side ways and up or down.

Panic Alarm (PA): A Device which when pressed causes a full alarm condition regardless of whether or not the alarm system is set/unset. This may be enabled to cause a silent alarm if the system is monitored, then having the same effect as Duress code.

Partition: Segmented section of a security system.

Passive Infra-Red Receiver (PIR): Is an electronic device which measures infrared light radiating from objects in its field of view. PIRs are often used in the construction of PIR-based motion detectors. Apparent motion is detected when an infrared source with one temperature, such as a human, passes in front of an infrared source with another temperature, such as a wall.

Peak-to-Peak: The amplitude difference between the most positive and the most negative excursions of a signal.

Phase Alternating Line system (PAL): A color television system used in Europe, Australia, parts of Africa and the Middle East. It has 625 horizontal scan lines and 25 frames per second.

Photo Electric Beam (PEB): is a device used to detect the presence of an object by using a light transmitter, often infrared, and a photoelectric receiver. There are three functional types. An opposed arrangement consists of a receiver located within the line-of-sight of the transmitter. In this mode, an object is detected when the light beam is blocked from getting to the receiver from the transmitter. A retro-reflective arrangement places the transmitter and receiver at the same location and uses a reflector to bounce the light beam back from the transmitter to the receiver. An object is sensed when the beam is interrupted and fails to reach the receiver. A proximity-sensing arrangement is one in which the transmitted radiation must reflect off of the object in order to reach the receiver. In this mode, an object is detected when the receiver sees the transmitted source rather than when it fails to see it.

Picture Element (Pixel): Photo sensor site in an image sensor like CCD chip; converts the input light image to an electronic signal.

Pinhole Lens: A lens with a relatively small front opening so it can be used in covert application.

Pixel Picture Element: Photo sensor site in an image sensor like a CCD chip; converts the input light image to an electronic signal.

Point-to-Point Protocol (PPP): For communications between two computers using a serial interface.

Point-to-Point Protocol over Ethernet (PPPoE): Pre-sets the pre-positioning of pan, tilt and zoom cameras by the use of potentiometers in the moving parts of the camera head. These allow the control equipment to store and move to a set reference point when the controller dictates or when an alarm exists.

Power Supply Unit (PSU): Is a device or system that supplies electrical or other types of energy to an output load or group of loads. Preventative Maintenance: An security engineer's attendance to inspect a system to verify all devices are working properly.

Public Switched Telephone Network (PSTN): Quad Splitter Combines up to 4 video inputs into one channel and displays them on one monitor screen split into 4.

Push To Set (PTS): A button which when activated triggers the final setting of the Alarm system.

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There are no definitions under the letter "Q" at this time.

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Radio Corporation of America (RCA): Conveniently used to describe phone jack and plug, one of the audio/video connectors.

Random Access Memory (RAM): The place in a computer where the operating system, application programs, and data in current use are kept temporarily so that they can be quickly reached by the computer's processor.

Remote Keypad (RKP): A non-fixed keypad that can trigger and alarm from a defined distance to the control panel.

Remote Line Expander (RLE): A non-fixed device that expands the lines range.

Remote Reset: The facility to apply an engineer reset to system without physical attendance.

Repeater: Is an electronic device that receives a signal and retransmits it at a higher level or higher power, or onto the other side of an obstruction, so that the signal can cover longer distances without degradation.

Retinal Scan: Is a biometric technique that uses the unique patterns on a person's retina to identify them. It is not to be confused with another ocular-based technology, iris recognition.

Router: A device on the Internet that determines the next network point to which a data should be forwarded.

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S-Video: Transmits luminance and color portions separately, using multiple wires, thus avoiding the color encoding process and its inevitable loss of picture quality.

Sequential Couleur A'Memorie (SECAM): A color television system used in France, Russia and other countries that do not use either the NTSC or PAL system. It has 625 horizontal scan lines and 25 frames per second. Sequential Switcher: Video Switcher. A device that allows the video signals from multiple cameras to be displayed on a monitor, or recorded on a VCR one at a time in sequence.

Server: A computer program that provides services to other computer programs in the same or other computers. Or, the computer that a server program runs.

Shielded Wire: Is an electrical cable of one or more insulated conductors enclosed by a common conductive layer. The shield may be composed of braided strands of copper (or other metal), a non-braided spiral winding of copper tape, or a layer of conducting polymer. Usually, this shield is covered with a jacket. The shield acts as a Faraday cage to reduce electrical noise from affecting the signals, and to reduce electromagnetic radiation that may interfere with other devices. The shield minimizes capacitively coupled noise from other electrical sources. In single conductor signal cables the shield may act as the return path for the signal and is usually connected only at the signal source. In multiconductor cables the shield should be grounded only at the source end, and will not carry circuit current High voltage power cables with solid insulation are shielded to protect the cable insulation and also people and equipment.

Signal-to-Noise Ratio (S/N Ratio): The ratio between the television signal and the noise; expressed in decibel (dB). The higher the number the better.

Silent Alarm: Is a burglar alarm that makes no noise that is audible to the trespasser. The alarm makes an audible noise elsewhere and notifies the police. A silent alarm may also be a panic button alarm.

Simple Mail Transfer Protocol (SMTP): TCP/IP used in sending and receiving e-mail.

Siren: is a loud noise maker

Smoke Detector: Is a device that detects smoke and issues an alarm to alert nearby people that there is a potential fire. A household smoke detector will typically be mounted in a disk shaped plastic enclosure about 150mm in diameter and 25mm thick, but the shape can vary by manufacturer. Because smoke rises, most detectors are mounted on the ceiling or on a wall near the ceiling. To avoid the nuisance of false alarms, most smoke detectors are mounted away from kitchens. To increase the chances of waking sleeping occupants, most homes have at least one smoke detector near any bedrooms; ideally in a hallway as well as in the bedroom itself. Smoke detectors are usually powered by one or more batteries but some can be connected directly to household wiring. Often smoke detectors that are directly connected to household wiring also have a battery as a power supply backup in case the household wiring goes out. It is usually necessary to replace the batteries once a year to ensure appropriate protection. Most smoke detectors work either by optical detection or by ionization, but some of them use both detection methods to increase sensitivity to smoke. Smoke detectors may operate alone, be interconnected to cause all detectors in an area to sound an alarm if one is triggered, or be integrated into a fire alarm or security system. Smoke detectors with flashing lights are available for the deaf or hearing impaired, although recent research suggests that their waking effectiveness is poor. A smoke detector cannot detect carbon monoxide to prevent carbon monoxide poisoning unless it has an integrated carbon monoxide detector.

Solid Wire: is cheaper to manufacture than stranded wire and is used where there is no need for flexibility in the wire. Solid wire also provides strength and protection against the environment.

Source Tagging: is the application of EAS security tags at the source, the supplier or manufacturer, instead of at the retail side of the chain. For the retailer, source tagging eliminates the labor expense needed to apply the EAS tags themselves, and reduces the time between receipt of merchandise and when the merchandise is ready for sale. For the supplier, the main benefit is the preservation of the retail packaging aesthetics by easing the application of security tags within product packaging. Source tagging allows the EAS tags to be concealed and more difficult to remove. The most common source tags are AM strips and 8.2MHz Radio Frequency Labels. Most manufacturers use both when source tagging. One significant problem from source tagging is something called "tag pollution" whereupon non-deactivated tags are carried around by customers causing unwanted alarms. The problem is that no store has both systems. Therefore if a store actually has an anti-shoplifting system to deactivate a label they will only deactivate one of the two. This is often the reason why people make an alarm entering a store and can cause great frustration for both customers and staff. The problem is most evident in shopping malls where customers float between stores. Retailers who use other types of loss-prevention systems than AM or 8.2MHz Radio Frequency systems will not be as affected by "tag pollution".

Stranded Wire: is composed of a bundle of small-gauge wires to make a larger conductor, which may optionally be insulated. Stranded wire is more flexible than a solid strand of the same total gauge.

Super Video Home System (SVHS): Super VHS; a higher quality extension of the VHS home videotape format.

Switcher Sequential Switcher or Video Switcher: A device that allows the video signals from multiple cameras to be displayed on a monitor, or recorded on a VCR one at a time in sequence.

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Terabyte (TB): Is a measurement term for data storage capacity. The value of a terabyte is based upon a decimal radix (base 10) and is defined as one trillion (short scale) bytes, or 1000 gigabytes.

Transmission Control Protocol (TCP): A set of rules to exchange messages with other Internet points at the information packet level. Transmission Control Protocol / Internet Protocol (TCP/IP): The basic communication language or protocol of the Internet.

Thin-Film Transistor (TFT): Is a variant of Liquid Crystal Display (LCD) which use's TFT technology to improve their image quality. TFT LCDs are one type of active matrix LCD, though this is usually synonymous with them. They are used in both flat panel displays and projectors. In computing, TFT monitors are rapidly displacing competing CRT technology, and are commonly available in sizes from 30 to 77 cm (~12 to 30 inches). As of 2006, they have also made inroads on the television market. There is no, or minor effect on the eyes, if we use TFT-LCD monitors.

Time and Date Generator: Installed between a CCTV camera and a monitor, it generates the information of Date, Time and camera ID.

Time Lapse VCR: A video recorder that can be set to record continuously over long period of time. This can be anything from two hours to 960 hours.

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Underwriters Laboratories (UL): Is a U.S. not-for-profit, privately owned and operated product safety testing and certification organization. Based in Northbrook, Illinois, UL develops standards and test procedures for products, materials, components, assemblies, tools and equipment, chiefly dealing with product safety. UL also evaluates and certifies the efficiency of a company's business processes through its management system registration programs. Additionally, UL analyzes drinking and other clean water samples through its drinking water laboratory in South Bend, Indiana. UL is one of several companies approved for such testing by the U.S. federal agency OSHA. OSHA maintains a list of approved testing laboratories, known as Nationally Recognized Testing Laboratories.

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Verification: The means of verifying that an intrusion has taken place. Can be either audio, visual or sequential means.

Victor Home System (VHS): Used by most VCRs as the recording medium - 240 lines resolution.

Video Band: The frequency band used to transmit a composite video.

Videocassette Recorder (VCR): A device that accepts signals from a video camera/microphone and records video/audio on magnetic tape in a cassette. The VCR can play back recorded video/audio on a television set or CCTV monitor.

Video Switcher: Switcher or Sequential Switcher. A device that allows the video signals from multiple cameras to be displayed on a monitor, or recorded on a VCR one at a time in sequence.

Viper: Trade name for a vibration/shock detector.

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Wavelet: A mathematical function useful in digital signal processing and image compression. In the Internet communications, wavelet has been used to compress images to a greater extent than is generally possible with other methods such as JPEG or MPEG.

Web Camera Server: A CCTV Camera with built-in web server computer.

Web Server: The computer program (housed in a computer) that serves requested HTML pages or files.

Wide Area Network (WAN): Is a computer network that covers a broad area (i.e., any network whose communications links cross metropolitan, regional, or national boundaries [1]). Or, less formally, a network that uses routers and public communications links [1]. Contrast with personal area networks (PANs), local area networks (LANs), campus area networks (CANs), or metropolitan area networks (MANs) which are usually limited to a room, building, campus or specific metropolitan area (e.g., a city) respectively. The largest and most well-known example of a WAN is the Internet.

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There are no definitions under the letter "X" at this time.

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There are no definitions under the letter "Y" at this time.

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Zoom Lens: A lens of continuously variable focal length

Zone: Identity of detection device(s) connected to an intruder alarm system. Segmented section of a fire system.

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