Start by selecting a basic shape from the drop down menu.
These are called 'open chords', and are the most common, and first chords you should learn. They are the building blocks apon which you can create any other chord!
By transposing them, or creating variations such as minor or seventh chords, you can build a wide variety of chords around each of the basic shapes. Be aware of a shape in relation to each chord built around it, and you'll quickly understand and remember the location and relationships of the many chord possibilities on the fretboard.