CMake is an open-source tool designed to manage the build process of software projects. It uses a simple configuration file, called CMakeLists.txt, to define project settings, dependencies, and build instructions. This allows developers to generate platform-specific build files, such as Makefiles or Visual Studio project files, making it easier to compile code across different operating systems. One of the key features of CMake is its ability to handle complex project structures and dependencies automatically. It supports various programming languages, including C++, C, and Fortran, and can integrate with other tools like CTest for testing and CPack for packaging. This flexibility makes CMake a popular choice among developers for managing large-scale software projects.