Computer programs are instructions for a computer. Usually, computer programs are in the form of a human-readable, computer programming language called source code. 17 USCS § 101 defines "computer program" as a set of statements or instructions to be used directly or indirectly in a computer in order to bring about a certain result. A software package is used in object-oriented programming to name a group of related classes of a program. Packages are useful to measure and control the inherent coupling of a program. They contain written programs or procedures or rules and associated documentation pertaining to the operation of a computer system and that are stored in read/write memory.