Squeak is released under Squeak-L. It is a very free license, though it does require you to share any modifications you make to the VM or the base classes. The license allows you to be your own OfficialSupport.
The Package Universes distributions include a number of packages pre-tested for the release and ready to install. They are a good basis for software development if you do not need bleeding-edge development versions of Squeak.
Errata
The list of known bugs and outstanding issues with the current stable release can be found at Squeak Errata.
What You Need
At a bare minimum, you need the following files to run Squeak:
A portable image file, containing a snapshot of Squeak
The .changes file for the specific image you choose.
Download sites vary in how they package these files; often, you will have to download platform-independent and platform-dependent files separately. Usually, the image and changes files are packaged together in a zip file, and the vm and sources files are in separate zips.
Notes:
Virtual machines and Squeak images are generally compatible up to major version changes. So a 3.4 and 2.8 VM and image will not work together, but 3.2 and 3.5 will.
If you are using an alpha release, you can download the very latest patches without waiting for the ftp sites to update; see: Code updates.
The general FTP repository
You can find all platform-independent files, as well as most of the platform-specific files, and also archival versions of Squeak at the Squeak FTP Site at ftp.squeak.org (or from Squeak FTP Mirrors). However, the platform (VM) sourcecode directories exist on the http://squeakvm.org/svn/squeak/ Subversion site for you to download.
