raylib - Cross-platform, open-source game development library in C.
Pygame - Pygame is a set of Python modules designed for writing games.
SFML - SFML provides a simple interface to the various components of your PC, to ease the development of games and multimedia applications. It is composed of five modules: system, window, graphics, audio and network.
GeeXLab - GeeXLab - cross-platform tool for game development, 3D programming, creative coding and prototyping
SDL - Simple DirectMedia Layer is a cross-platform multimedia library designed to provide low level...
LOVE 2D - Hi there! LÖVE is an *awesome* framework you can use to make 2D games in Lua.