RPi.GPIO API - An overview of the Python functions you can use to drive GPIO.GPIO Pinout - An overview of the Pi's GPIO header.
Here's a quick overview of what's covered: In this tutorial we'll show two different approaches to reading and driving the Raspberry Pi's GPIO pins: python and C. Whether you're a fan of the easily-readable, interpretive scripting language Python or more of a die-hard C programmer, you'll find a programming option that suits our needs. If you've never driven an LED or read in a button press using the Raspberry Pi, this tutorial should help to get you started. We've pared that list down, and ended up with two really solid, easy tools for driving I/O: Python and C (using the WiringPi library). Programming in what language? Take your pick! A quick glance at the Raspberry Pi GPIO examples shows that there are dozens of programming-language-choices. Driving the Raspberry Pi's I/O lines requires a bit of programming.