Beginner Guitar Chords Chart
These are the chords which beginners should start on. Most are relatively easy, except for C7, B7 and the Barre chords, which may take some extra time to get used to.
All the chords are "open" chords (which means they use at least one open string), except for the "barre" chords, which are the ones on the bottom row and "Major" and "7" on the row above that. They have a star in their lowest note signifying the "root note" of the chord, and they can be played anywhere up and down the neck, unlike open chords which are always played like they are here and not movable.
Barre chords are more advanced because you are required to press down on all the notes you hear, and should be learned a few months after you start learning guitar, otherwise you may get some straining problems in your wrist.
And these chords are used all the time by everybody, so you'll be using them forever.
Make sure that the fingertips of your left hand are not muting notes that shouldn't be muted - put your fingers in position and play each note from the lowest string to the highest string and let them all ring out.
If that sounds boring (it is), put on your favorite tv show and just try one chord per episode. You'll build up calluses on your fingertips in a few weeks so it won't hurt as bad.
The chords diagrams with X's on top of them show stings that should not be played. There's many techniques to getting those string to not ring out (basically muting them withe the left or right hand, or not stumming them), so if you're having a problem with them seek out a guitar teacher or internet video to show you how to get that right.