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This article is about the programming language. For the food, see bubble and squeak.

The Squeak programming language is a Smalltalk implementation, derived directly from Smalltalk-80, by Smalltalk's originators during their time at Apple Computer and later, at Walt Disney Imagineering, where it was intended for use in internal Disney projects. It is object-oriented, class-based, and reflective. Squeak is available for many platforms, and programs produced on one platform run bit-identical on all other platforms. The Squeak system includes code for generating a new version of the virtual machine (VM) it runs on. It also includes a VM simulator written in itself (Squeak). For this reason, it is easily ported.

Contents 1 Alan Kay 2 User interfaces 3 Uses 4 License 5 See also 6 External links 6.1 Books

Squeak incorporates many of the elements Alan Kay proposed in the Dynabook concept, which he formulated in the 1960s. Kay is an important contributor to the Squeak project.

Squeak has a number of user interfaces:

• An implementation of Morphic, Self's graphical, direct object-manipulation framework. This is Squeak's main interface.
  • Tile-based, limited visual programming scripting in eToys, based on Morphic.
  • A new, experimental interface called Tweak. In 2001, it became clear that the eToy architecture in Squeak had reached its limits in what the Morphic interface infrastructure could do. Hewlett-Packard researcher Andreas Raab proposed defining a "script process" and providing a default scheduling mechanism that avoids several more general problems[1]. The result was a new user interface, proposed to replace the Squeak Morphic user interface in the future. Tweak added mechanisms of islands, asynchronous messaging, players and costumes, language extensions, projects, and tile scripting[2]. Its underlying object system is class-based, but to users, during programming (scripting), it acts like it is prototype-based. Tweak objects are created and run in Tweak project windows.
• Model-View-Controller (MVC), the traditional interface of some languages such as Smalltalk-80 and Java, and for which Morphic is an alternative. This is for programmers who wish to use this older type of interface.

Kay, and many other Squeak contributors, collaborate on the open source Croquet project, which is built on Squeak, and offers a networked, real time, collaborative workspace with 2D and 3D abilities.

Squeak has been part of the computer science curriculum at the Georgia Institute of Technology for several years, and some faculty members take an active part in the growth and development of the language. It is commonly used as part of a course on object-oriented development due to its availability and features.

Squeak may be downloaded at no cost, including all its source code. There is some debate as to whether the Squeak license qualifies as free software or not, due to the presence of an indemnity clause in the original Squeak License. Version 1.1 of the environment, originally released on October 1997 under the Squeak License, has been released in May 2006 under the open source Apple Public Source License. It has been relicensed under the Apache License allowing inclusion in the One Laptop Per Child initiative. [3]

• Croquet project

• Squeak.org
• "History of Squeak"
• Open Directory: Squeak
• Squeakland.org
• Squeak Swiki
• SqueakCMI Swiki Champaign, IL
• (Spanish) "Small-Land"
• On Smalltalk -(fan blog)

• Downloadable books about Smalltalk Permission obtained to make these books freely available. Over a dozen full texts scanned from print.)
• Programando con Smalltalk - Un ambiente de objetos vivos Book in Spanish by Diego Gomez Deck.