MATV :
Multiple Access Television. The method of distributing TV signals by broadcasting them through the air.
MB :
Megabyte
Mbps :
Megabits per second. A measure of bandwidth.
Mini-DIN :
Multi-wire cable with Mini-DIN connectors at both ends. Usually has 4 inner wires. Pictures of Mini-DIN connectors.
Monochrome Signal :
Black and White signal.
MOD (Minimum Object Distance) :
The closest distance a lens will be able to focus upon an object. Wider angle (shorter focal length) lenses generally have a smaller MOD than larger focal length (narrower angle) lenses.
MOS :
Metal-oxide Semiconductor. One of video image chips like CCD, but it produces lower quality video.
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.
MPEG :
Moving Picture Experts Group. A standard for a digital video & audio compression.
Multiplexer :
This is a device that takes inputs from 2 or more video channels and combines them into one signal. This is often done by using time division multiplexing, which interleaves frames from each channel in such a way that they can be split out again. Frequency division multiplexing uses different frequencies to achieve the separation of the signals.
Mega Pixel Resolution :
Mega Pixel resolution refers to video resolutions now achievable using IP Cameras. Unlike Analogue cameras, whose resolution is usually limited to around 752 x 582 (0.4 Mega Pixels), a Mega Pixel IP Camera can achieve far greater resolutions such as 1280 x 1024 (1.3 Mega Pixels) or 1600 x 1280 (2 Mega Pixels).This increase in resolution produces far better image quality than a traditional analogue camera could ever achieve.
Motion Detection :
Recording method for digital surveillance systems. When someone walks in front of a camera, the pixels change and the DVR defines this as motion. The surveillance system will then record these images to the hard disk. This is a popular recording setup as every event recorded is actually motion driven as opposed to a static image if the system was set to record 'round-the-clock'.
Magnetic Contact :
A device that sends a signal when the magnetic field between two monitored points is broken.
Magnetic Lock :
A door lock made up of an electromagnet and a strike plate. The electromagnet is mounted in the door frame; the strike plate in the door. When power is applied to the electromagnet, the strength of the electromagnet keeps the door locked.
Magnetic Stripe Card :
An access control card with a strip of recordable magnetic material, on which data is encoded. Magnetic Stripe Reader, A reader capable of reading and interpreting cards using magnetic stripes to encode data.
Master Code Card :
An access control card that grants access and exit at every card reader on the system.
Memory :
The section of a host computer or a controller in which data and instructions are stored.
Modem :
A communication device that converts computer serial data to an analog format that can be transmitted and received via telephone.