(Originally "Schemer", by analogy with Planner and Conniver). A small, uniform Lisp dialect with clean semantics, developed initially by Guy Steele and Gerald Sussman in 1975. Scheme uses applicative order reduction and lexical scope. It treats both functions and continuations as first-class objects.
One of the most used implementations is DrScheme, others include Bigloo, Elk, Liar, Orbit, Scheme86 (Indiana U), SCM, MacScheme (Semantic Microsystems), PC Scheme (TI), MIT Scheme, and T.
See also Kamin's interpreters, PSD, PseudoScheme, Schematik, Scheme Repository, STk, syntax-case, Tiny Clos, Paradigms of AI Programming.
There have been a series of revisions of the report defining Scheme, known as RRS (Revised Report on Scheme), R2RS (Revised Revised Report ..), R3RS, R3.99RS, R4RS.
Mailing list: email@example.com.
[IEEE P1178-1990, "IEEE Standard for the Scheme Programming Language", ISBN 1-55937-125-0].