Software definitions determine classification of programs, documentation and operating systems for legal and regulatory treatment. Definitions of software center on the non-hardware programs and associated materials used with hardware, including program code, routines, documentation and the operating system. Reference works describe software as the totality of programs usable on a computer together with associated documentation, while legal classification queries focus on whether manuals and procedural guides are integral parts of the software product or ancillary reference material for regulatory and treatment purposes.