The lp command is used on many Unix-like systems to assign jobs to printer queues. The name derives from "lineprinter", though it has become the commonly used command for any sort of printer. The command originally appeared as part of the System V printing system, and for some time served as a shibboleth to distinguish between SysV and BSD systems.
The LPRng project provides lp as a simple wrapper to the lpr command.
Plan 9 from Bell Labs uses a command called lp for printing, though its functionality is somewhat different and simplified from the System V version. It is actually written as an rc shell script.
