A .cpp file is a source code file written in the C++ programming language. It contains human-readable instructions that a compiler translates into machine-executable code. C++ is a powerful, general-purpose programming language widely used for developing operating systems, game engines, high-performance applications, and embedded systems. The code within a .cpp file typically consists of variable declarations, function definitions, class definitions, and control structures. These elements work together to define the behavior of a program. Before a .cpp file can be executed, it must be compiled using a C++ compiler, such as GCC, Clang, or Microsoft Visual C++. The compilation process converts the source code into object code, which is then linked with other object files and libraries to create an executable file. C++ supports object-oriented programming principles, allowing developers to create modular and reusable code. Header files (typically with a .h or .hpp extension) are often included in .cpp files to provide declarations of functions, classes, and other entities defined in separate files, promoting code organization and reusability.