CLEO (CLEO Library) is a popular modding library for Grand Theft Auto: San Andreas, created by a team of dedicated developers. CLEO allows modders to create custom scripts, modify game mechanics, and add new features to the game without altering the original game files. This library provides a framework for modders to build upon, making it easier to create and manage mods. CLEO has become a staple in the GTA: San Andreas modding community, enabling the creation of a wide range of mods, from simple tweaks to full-fledged overhauls.