Much of learning ukulele is learning how to play chords. A chord is several notes played at once. Each string of the ukulele is a separate note, and strumming plays 4 notes at the same time.
To play a chord, hold down frets with your left hand and strum all 4 strings with your right hand. Holding down frets shortens strings, produces different notes, and allows you to play different chords. (Side note: You can play the Am7 chord without holding down any frets since the ukulele is tuned G, C, E, A, and the notes in the Am7 chords are G, C, E, A.)
I recommend starting with these 4 beginner ukulele chords: Am, C, F, G. This allows you to play most pop songs! Here’s more info on the basic music theory for understanding pop songs. Here are the chord diagrams:
Reading ukulele chord diagrams is easy. The thick black line represents the top of the ukulele, and the dots are where you put your fingers on the fretboard.
Here’s how I play the chords:
These chords are easy on the ukulele because of how it’s tuned. If you’re starting with a baritone ukulele or a guitar, I recommend starting with these 4 chords instead: Em, G, C, D.