Introduction
Parrot is a language-neutral virtual machine for dynamic languages such as Ruby, Python, PHP, and Perl. It hosts a powerful suite of compiler tools tailored to dynamic languages and a next generation regular expression engine. Its architecture differs from virtual machines such as the JVM or CLR, with optimizations for dynamic languages, the use of registers instead of stacks, and pervasive continuations used for all flow control.
The name "Parrot" was inspired by Monty Python's Parrot sketch. As an April Fools' Day joke in 2001, Simon Cozens published "Programming Parrot", a fictional interview between Guido van Rossum and Larry Wall detailing their plans to merge Python and Perl into a new language called Parrot (http://www.perl.com/pub/a/2001/04/01/parrot.htm).
Parrot Intermediate Representation (PIR) is Parrot's native low-level language. PIR is fundamentally an assembly language, but it has some higher-level features such as operator syntax, syntactic sugar for subroutine and method calls, automatic register allocation, and more friendly conditional syntax. Parrot libraries -- including most of Parrot's compiler tools -- are often written in PIR. Even so, PIR is more rigid and "close to the machine" than some higher-level languages like C, which makes it a good window into the inner workings of the virtual machine.
Parrot Resources
The starting point for all things related to Parrot is the main website http://www.parrot.org/. The site lists additional resources, well as recent news and information about the project.
The Parrot Foundation holds the copyright over Parrot and helps support its development and community.
Documentation
Parrot includes extensive documentation in the distribution. The full documentation for the latest release is available online at http://docs.parrot.org/.
Mailing Lists
The primary mailing list for Parrot is parrot-dev.parrot-dev@lists.parrot.org If you're interested in developing Parrot, the parrot-commits and parrot-tickets lists are useful. More information on the Parrot mailing lists, as well as subscription options, is available on the mailing list info page http://lists.parrot.org/mailman/listinfo.
The archives for parrot-dev are available on Google Groups at http://groups.google.com/group/parrot-dev and as NNTP at nntp://news.gmane.org/gmane.comp.compilers.parrot.devel.
IRC
Parrot developers and users congregate on IRC at #parrot on the irc://irc.parrot.org server.
It's a good place to ask questions or discuss Parrot in real time.
Issue Tracking & Wiki
Parrot developers track bugs, feature requests, and roadmap tasks at https://trac.parrot.org/, the open source Trac issue tracker. Users can submit new tickets and track the status of existing tickets. The site also includes a wiki used in project development, a source code browser, and the project roadmap.
Parrot Development
Parrot's first release occurred in September 2001. The 1.0 release took place on March 17, 2009. The Parrot project makes releases on the third Tuesday of each month. Two releases a year — occuring every January and July — are "supported" releases intended for production use. The other ten releases are development releases intended for language implementers and testers.
Development proceeds in cycles around releases. Activity just before a release focuses on closing tickets, fixing bugs, reviewing documentation, and preparing for the release. Immediately after the release, larger changes occur: merging branches, adding large features, or removing deprecated features. This allows developers to ensure that changes have sufficient testing time before the next release. These regular releases also encourage feedback from casual users and testers.
Licensing
The Parrot foundation supports the Parrot development community and holds trademarks and copyrights to Parrot. The project is available under the Artistic License 2.0, allowing free use in commercial and open source/free software contexts.