Arc is a new dialect of Lisp, being researched and developed, starting in 2001, and first released in January 2008, by noted Lisp programmer, entrepreneur, venture capitalist, and author, Paul Graham, and MIT computer scientist Robert Tappan Morris. Arc is intended to be a terse Lisp, fully reworked from the axioms up, highly plastic, malleable, modifiable, "hackable", and to stay in productive use for decades. Several essays, on the Web and in a book, describe aspects, features, and goals for Arc. Some projects, internal and public, at venture startup Y Combinator are coded in it, such as the Hacker News web forum and news aggregator program. Arc is open source, via a Perl Artistic License.
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