Since its introduction in 1985, the PostScript language has been considerably extended for greater programming power, efficiency, and flexibility.
Typically, these language extensions have been designed to adapt the PostScript language to new imaging technologies or system environments. While these extensions have introduced new functionality and flexibility to the language, the basic imaging model remains unchanged.
PostScript Level 2 integrates the original PostScript language, all previous language extensions, and new language features into the core PostScript language imaging model.