2D is the same is 3D but with less D.
Simple DirectMedia Layer (SDL) is a cross-platform development library. Template project is in the repository at /sdlbase.
Platforms: Windows, OSX and Linux.
Written in C.
Input support from keyboard, mouse and joystick.
Graphic and can also support OpenGl.
Sol's Graphics for Beginners - 2005
Flawless alternative to SDL - 2010