Guile Scheme is a general-purpose, high-level programming language whose flexibility allows expressing concepts in fewer lines of code than would be possible in languages such as C. For example, its hygienic macro system allows adding domain specific syntax-elements without modifying Guile.

The core idea of Guile Scheme is that "the developer implements critical algorithms and data structures in C or C++ and exports the functions and types for use by interpreted code.

The standard distribution offers modules for Portable Operating System Interface (POSIX) system calls, scheduling, a foreign function interface, S-expression based XML processing through SXML, SXPath, and SXSLT, HTTP and other World Wide Web APIs, delimited continuations, array programming,[11] and other functionality.

[16] A brief summary follows: After the success of Emacs in the free software community, as a highly extensible and customizable application via its extension (and partly implementation) language Emacs Lisp, the community began to consider how this design strategy could apply to the rest of the GNU system.

From several contributions in several Usenet newsgroups, Lord controversially chose Guile from a suggestion by Lee Thomas.

Various attempts at this have been made in past versions: a dialect of Scheme essentially differing only in its C-like syntax, a translation of Emacs Lisp, a Tcl converter motivated by tkWWW, and something roughly resembling the language Logo.

According to the release announcement by Andy Wingo, real-world programs often showed a speedup of 30% or more with Guile 2.2 when compared to the previous 2.0 series.

Guile 2.2.0 also lowered memory usage, sped up the "eval" interpreter, provided better support for multi-core programming, and removed any fixed limit on recursive function calls.