Squeak

Squeak is an object-oriented, class-based, and reflective programming language. It was derived from Smalltalk-80 by a group that included some of Smalltalk-80's original developers, initially at Apple Computer, then at Walt Disney Imagineering, where it was intended for use in internal Disney projects. The group would later go on to be supported by HP Labs, SAP, and most recently, Y Combinator. Squeak runs on a virtual machine (VM), allowing for a high degree of portability. The Squeak system includes code for generating a new version of the VM on which it runs, along with a VM simulator written in Squeak.