Free Pascal

Free Pascal is a freely distributed compiler of the Pascal programming language.

An important feature of this compiler, unlike, for example, GNU Pascal, is its focus on common commercial dialects of the language: Object Pascal and Delphi.

Free Pascal supports several compilation modes to make it compatible with different dialects and language implementations.

• TP - Turbo Pascal compatibility mode: near-total compatibility, except for a few things: the FPC compiles programs for protected processor mode, where direct access to memory, ports, etc. is not possible.
• FPC - its own dialect: corresponds to the previous one, extended with additional features, such as, for example, overloading operations.
• DELPHI - Borland Delphi compatibility mode: includes class and interface support.
• OBJFPC - Combines object-oriented features of Delphi with the language's own extensions.
• MACPAS - Mac Pascal compatibility mode.