Magazine Format – A program made up of varied segments on a variety of subjects or themes.

Mailing List – A automated system that allows people to send e-mail to one address, whereupon their message is copied and sent to all of the other subscribers to the list.

Major Television Market – Usually refers to one of the top 50 television markets (DMAs) in the U.S. in terms of the number of TV households reported by Nielsen Media Research.

Make Good – The commercial time given to advertisers either because an advertisement was preempted or did not receive the exposure that had been agreed to and paid for. (See also, Bonus Spot.)

Master – An original recording from which copies are made.

Master Antenna (MATV) – A single receiving system serving multiple television receivers within the same building or group of buildings.

MDS – See Multipoint Distribution System

Media Mix – The distribution of time and money allocated among TV, radio, print and Internet advertising that makes up the total advertising budget of an advertiser, agency or media buyer.

Media Modeling - the process of quantitatively estimating audience behavior. Modeling is usually contrasted with the process of direct measurement in which meters, diaries, surveys or coincidentals are used to measure the behavior. Typically when viewing behavior is modeled, a set of measures is adjusted to represent a geographic area, demographic category or consumer target for which there is no direct measurement. Modeling in the broader sense may include any mathematical technique for combining or imputing data, such as ascription, fusion or weighting.

Meter – Any automatic recording device which, when connected to a television set, will monitor the tuning status of that TV set (set on/off, time, duration and channel).

Metro Area – See Metropolitan Statistical Area

Metropolitan Statistical Area – Defined by the Office of Management and Budget. It has a large population nucleus, together with adjacent communities that have a high degree of economic and social integration with that nucleus. Also known as Metro Area.

Microwave Relay System – A system of radio repeaters mounted on towers, usually spaced up to 50 miles apart, and each consisting of a receiver and transmitter. They are used to interconnect television stations and cable systems. Microwave technology also is used to connect studios to transmitters and for remote television originating equipment to the studio or transmitter, usually used for live news and sports coverage.

Miniseries – Long duration programs with a continuing plot line, made for television and shown as a series of episodes on different evenings.

MMDS – See Multichannel Multipoint Distribution Service

Modem – An electronic device or program that enables a computer to transmit data to another computer via telephone lines.

MSO -- Multi-System Operator; A company that owns and/or operates more than one cable system.

Multi-channel Multi-point Distribution System (MMDS) – This technology is a carrier service for short distance line of sight transmission of a TV programming to selected locations. Subscribers use a specialized antenna and converter combination to receive the signal, which may be scrambled to prevent unauthorized reception.

Multipoint Distribution Service (MDS) – A common carrier service used to transmit private TV programming or data to locations within a metropolitan area. It is used to transmit special TV channels to hotels, and to transmit pay TV programs to cable systems.

Multiplexing – The simultaneous transmission, through digital compression technology, of multiple television programs on the same channel. In more traditional cable television parlance, multiplexing refers to the use of two or more channels to present the same lineup but at different times on each channel.

Multiple Ownership Rules (Also called National Broadcast Ownership Limits) – FCC regulations limiting broadcast station ownership by any single entity. The rules currently limit a broadcast entity from owning stations covering more than 35% of U.S. TV homes.

Must-Carry Rule –– An FCC requirement that a cable system carry certain qualified local TV commercial stations and non-commercial educational TV stations as follows: (1) a cable system with 12 or fewer usable activated channels shall carry the signals of at least 3 local commercial stations and one non-commercial station; (2) a cable system with more than 12 usable activated channels shall carry the signals of local commercial television stations up to one-third of the aggregate number of usable activated channels of such system; (3) a cable system with 13 to 36 usable activated channels shall carry no more than 3 non-commercial stations; and (4) a cable system with 37 or more usable activated channels shall carry all non-duplicative non-commercial stations that request carriage.

Multi-System Operator (MSO) – A company that owns and/or operates more than one cable system.