In this Instructable I will show you how to get a very basic GPIO system working with your Raspberry Pi.
For this I will focus on simply controlling an LED.
NOTE: For controlling GPIO via a web browser, click here.
Step 1: GPIO Pinouts
Please note that the DNC connections are actually connected on the board - so don't put voltage on them :D
To turn pin 7 of the header connector on, you set GPIO 4 high.
Note: You can find another pinout image, here.