This is a half note strum.It lasts for two beats. There are two half note strums in one bar of * time.
This is a quarter note strum. It lasts for one beat. There are four quarter note strums in one bar of * time.
These are a pair of eighth note strums. Each strum lasts for half a beat. There are eight eighth note strums in one bar of * time. Play the larger downward strum louder.
These Strums are a group of sixteenth note strums. Each strum lasts for one quarter of a beat. There are sixteen sixteenth note strums in one bar of * time. Play the larger downward strum louder.