GPC distributions now include a number of useful Pascal units and a complete set of BP compatibility units – except for the Graph unit (which is currently distributed separately due to its license) and the OOP stuff. The main use of these units is to provide a way to port BP programs to GPC as easily as possible. Some of the units also implement functionaliy not available otherwise.
Most of the BP compatibility units – except CRT and Printer – are merely meant to let programs written for BP compile with GPC as easily as possible. They should not be used in newly written code, and for code ported from BP to GPC, it is suggested to replace them successively with the more powerful – and often easier to use – alternatives that GPC's Run Time System (see Run Time System) offers.
The following sections describe all units included with GPC (besides the GPC module which describes the interface to the Run Time System, Run Time System).