A p-code is similar to a byte-code but a p-code works at a higher level. Whereas byte-codes work at a very low level similar to machine code, p-codes can perform moderately complex tasks such as printing a message or clearing the screen. Some implementations of BASIC and Pascal use p-codes that are translated by a just-in-time compiler to actual machine instructions.

The Business Operating System (BOS) of the 1980s was a cross-platform operating system designed to exclusively run p-code based programs.

See also

• P-Code machine
• UCSD p-System