VSLisp is an embedded Lisp library and standalone interpreter. It's
very small, and runs on many platforms. It was developed as a graphics
scripting language for VMS, but now its development goes under Unix,
and old Graph library is not supported now.

VSLisp is not Scheme or Common Lisp compatible. Surely, you can
customize it to look like one of them, but by default VSLisp is a yet
another Lisp dialect, and to work with it you'll need to understand
the difference.

VSLisp is distributed under the terms of the GNU General Public License
version 2.