Many pop songs are written in C Major Scale. When you know how to play these basic chords and progressions it becomes a lot easier to recognize them in songs !
It is common to number the chords, starting with the I (roman 1) for the first chord in the scale.
For C major, the I chord is obviously C major.
A chord progression that is seen in a lot of pop and blues songs is I-IV-V
In the scale of see this would be:
I: C Major
IV: F Major
V: G Major
Have a go at playing these chords and it will probably immediately sound familiar ! :)