Playing rhythms is particularly difficult for pianists because we often play different rhythms in each hand! These exercises will help ANY musician (not just pianists) to feel rhythm internally and play as ONE cohesive rhythm, but with two limbs. [suitable for beginners and non-music readers!]
When you first decided to learn piano you probably didn't imagine you'd need to learn rhythmic skills, but once you get into creative playing that's exactly what you need to develop! So why is it so difficult to get our hands playing different things?