Maude is a high-performance reflective language and system supporting both
equational and rewriting logic specification and programming for a wide range
of applications. Maude has been influenced in important ways by the OBJ3
language, which can be regarded as an equational logic sublanguage. Besides
supporting equational specification and programming, Maude also supports
rewriting logic computation.

Rewriting logic is a logic of concurrent change that can naturally deal with
state and with concurrent computations. It has good properties as a general
semantic framework for giving executable semantics to a wide range of
languages and models of concurrency. In particular, it supports very well
concurrent object-oriented computation. The same reasons making rewriting
logic a good semantic framework make it also a good logical framework, that
is, a metalogic in which many other logics can be naturally represented and
executed.

Maude supports in a systematic and efficient way logical reflection. This
makes Maude remarkably extensible and powerful, supports an extensible algebra
of module composition operations, and allows many advanced metaprogramming and
metalanguage applications. Indeed, some of the most interesting applications
of Maude are metalanguage applications, in which Maude is used to create
executable environments for different logics, theorem provers, languages, and
models of computation.