It is the C6 chord.
There are literally hundreds of them, which ones are you interested in? There are chord charts available on most ukulele web sites.
You hold down the 1st string 2nd fret, 2nd string 3rd fret, 3rd string 2nd fret. The tab for it would look like this: XXXX X0X0 XX0X
C Major- G Major- A Minor- F Major over and over. Use a simple strumming pattern like down, down up, up down repeated.
I find it a difficult chord to make, but here is the tab for the B chord: 0000 00XX 0X00 X000 I find it easiest to bar the 2nd fret and then use the second finger on the 3rd string and the ring...