Look Ahead Left-to-right parse, Rightmost-derivation (algorithm) (LALR, Look ahead LR) A type of LR parser that can deal with more context-free grammars than SLR parsers but less than LR[1] parsers. LALR parsers are popular because they give a good trade-off between the number of grammars they can deal with and the size of the parsing table required.
Compiler compilers like yacc and Bison generate LALR parsers. Wikipedia. Last updated: 2003-05-13