There are many places to find chord charts: pretty much every ukulele book contains a set of chord diagrams. What makes Mike’s chart unique is that it’s organized by frequency of use. Common chords, like the chords featured in the “Four Chord Song,” are listed first. Rare chords, like G#SUS4, are listed at the bottom, since you’ll rarely see them used. This type of frequency analysis is very, very useful: the power law applies to music as well. To be able to play songs, you don’t need to know hundreds of chords. Ten to twelve chords cover most songs.