the ieee 1364-2001 standard, nicknamed `verilog-2001, is the first major update to the verilog language since its inception in 1984. this book presents 45 significant enhancements contained in verilog-2001 standard. a few of the new features described in this book are: ansi c style port declarations for modules, primitives, tasks and functions; automatic tasks and functions (re-entrant tasks and recursive functions); multidimensional arrays of any data type, plus array bit and part selects; signed arithmetic extensions, including signed data types and sign casting; enhanced file i/o capabilities, such as $fscanf, $fread and much more; enhanced deep submicron timing accuracy and glitch detection; generate blocks for creating multiple instances of modules and procedures; configurations for true source file management within the verilog language. this book assumes that the reader is already familiar with using verilog. it supplements other excellent books on how to use the verilog language, such as the verilog hardware description language, by donald thomas and philip moorby (kluwer academic publishers, isbn: 0-7923-8166-1) and verilog quickstart: a practical guide to simulation and synthesis, by james lee (kluwer academic publishers, isbn: 0-7923-8515-2).