Abstract syntactical tree
Abstract syntactical tree. Other names: Kantorovich's tree, Abstract Syntax Tree (AST). AST is a finite oriented tree the nodes of which are correlated with the programming language's operators, and the leaves - with the corresponding operands. Thus, the leaves are empty operators and serve only as variables and constants. AST differs from the parse tree in that it keeps only the essential information about the program while the parse tree, on the contrary, contains much unnecessary information. In this sense the abstract syntactical tree is a condensed form of the parse tree convenient for presenting the language constructions' structure from the semantics' viewpoint.
- Wikipedia "Abstract syntax tree"