It was designed to have an exceptionally clear and simple semantics. A wide variety of programming paradigms, including imperative, functional, and message passing styles, find convenient expression in Scheme. Arbitrary precision integers are supported if GMP is installed. A new datatype called mapping . It behaves almost lika vectors, except that you may reference it using other types than integers.
Mappings are in many cases almost as fast as vectors.
Identifiers are case sensitive. Strings are always immutable, e.i. The compiler is, almost, two-pass. Strings and symbols are shared. Eval compiles its expression before evaluating it.