The .prg file extension is a versatile format primarily used to store program source code or executable binary data across various computing platforms. Historically, it is most recognized as the standard executable format for 8-bit Commodore home computers, including the Commodore 64 and VIC-20, where the file contains a specific memory load address followed by binary machine code. In the professional database industry, .prg is the standard extension for source code files written in xBase languages such as dBase, FoxPro, and Clipper. In this context, the files are typically plain text and contain procedural logic, function definitions, and database commands used to automate data management tasks. Furthermore, the extension is occasionally utilized by specialized industrial equipment, such as CNC machines and programmable logic controllers (PLCs), to hold instruction sets. Because the extension is generic, the internal structure of a .prg file depends entirely on the software that created it, ranging from human-readable scripts to compiled binary instructions.