M

megahertz (MHz)
One hertz equals one cycle of a wave per second. One MHz equals 1 million cycles per second.

modem
The term "modem" is a contraction for modulator/demodulator. They are used to convert binary data into analog signals suitable for transmission across a telephone network.

modulation
Modulation is the process of modifying the form of a carrier wave (electrical signal) so that it can carry intelligent information on some sort of communications medium.

Moving Pictures Experts Group, Layer-3 (MP3)
MP3 stands for MPEG Layer-3, which is an extension of the Motion Picture Experts Group (MPEG) standards for compressed digital video. MP3 is the most popular compression format for digital audio files, and is commonly used to distribute music over the Internet.

multiplexer (MUX)
A MUX is a device that transmits multiple signals over the same physical medium. Multiple signals are fed into a MUX and combined to form one output stream.

multiplexing
Multiplexing is a technology that allows multiple signals to travel over the same physical medium. Multiple signals are fed into a multiplexer and combined to form one output stream.

multistation access unit (MAU)
A MAU is a device used in Token Ring networks to provide connectivity between individual workstations. It is also called a Token Ring hub.