Scheme

A scheme is a plan or a system of related parts. The word comes from the Latin schema which means "figure". Special meanings of the word include the following

• A schema is a document for a plan, commonly used in ontology (computer science)
• The Scheme programming language is a dialect of Lisp.
• In mathematics, schemes are an important concept connecting the fields of algebraic geometry, commutative algebra and number theory. See scheme (mathematics).
• A specific technological technique

In digital technology you have such schemes:

e.g. MP3 encoding/decoding schemes, compression/decompression schemes, and modulation/demodulation schemes