FM

1. Short for Frequency Modulation, FM encoding is a method of recording data to a floppy disk and/or hard disk drive platter. This method of encoding is no longer used today and has been replaced with MFM.
2. When referring to the radio or an audio signal , FM is short for Frequency Modulation. FM is a method of transmitting a signal of greater quality at ranges of 80 MHz to 108 MHz at a shorter distance when compared to AM.

Also see:  AM, Hard disk drive definitions, MFM