Last updated at 7:21 pm UTC on 31 December 2015
The usual meaning of "Smalltalk" is either the Squeak programming language or the historical programming environment that Squeak derives from. Note that the "t" in Smalltalk isn't capitalized.
Squeak is a descendent of Smalltalk-80. The core developers of Squeak (Squeak Central) in fact include many of the core developers of Smalltalk-80.
Squeak's language and much of the class library is identical to that of Smalltalk-80: they both have objects, classes, single inheritance, blocks, garbage collections, collections, streams, model-view-controller, and many other bits.
ANSI Smalltalk is a recognized standard for Smalltalk. While Squeak is Smalltalk in spirit, it is not currently (2003) compliant with the ANSI Smalltalk standard. There is temporarily an add-on on SqueakMap which tries to move Squeak towards ANSI compatibility.
Also see: Smalltalk overview Squeak's programming language Squeak websites Smalltalk & Squeak books Camp Smalltalk Improving Smalltalk
Smalltalk global variable