Run-length limited encoding

A fast and highly efficient method of storing data on a disk (usually a hard disk) in which patterns in the bits representing information are translated into codes rather than being stored literally bit by bit and character by character. In RLL encoding, changes in magnetic flux are based on the number of zeros that occur in sequence. This scheme allows data to be stored with fewer changes in magnetic flux than would otherwise be needed for the number of data bits involved and results in considerably higher storage capacity than is possible with older technologies, such as frequency modulation (FM) and modified frequency modulation (MFM) encoding. Abbreviation: RLL encoding. Compare frequency modulation encoding, modified frequency modulation encoding.