Source : Free On-Line Dictionary of Computing

Look Ahead Left-to-right parse, Rightmost-derivation
     
         (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 (http://www.wikipedia.org/wiki/LALR_parser)}.
     
        (2003-05-13)