If you would like to learn to play the guitar, is one of the greatest websites where you can start. It has well structured lessons from the ground up, and you can watch most of that for free.

One important part of the beginners course is to improve your listening skills so that you can differentiate between chords qualities (major, minor, 7) and chord shapes.

I have created a small browser-based app if you would like to practice more, with your guitar away: