Musicians are inherently concerned with rhythm.
In fact, the mark of a natural talent is often their ability to understand, distinguish, and play a complicated rhythm – often intuitively. It makes sense, really. Rhythm is, after all, the part of music dealing with how sounds vary over time and their duration throughout it. Having natural rhythm is what some refer to as being able to keep the beat, and without some sort of beat a song is little to nothing (with the exception of some incredible experimental music that aims to get rid of rhythm altogether).
Some of us musicians, however, were not gifted with a great sense of rhythm — me included. I had to really work at learning various rhythms, while melody and harmony were no problem. Eventually I even created a course based on what I had learned called “Rhythm Piano” that reveals a “baseline” which makes knowing which note is played when much easier. It also covers many piano rhythms including:
Waltz, March, Swing, Ballad, Fiddle Jig, Rubato, Disco, Foxtrot, Stride, Triplet Patterns, The Shuffle, Gospel Waltz, Royal March, Polish Dance, Polka, Scotch Snap, Hungarian Skip, Rhythm & Blues, Western, Boogaloo, Hornpipe, Gigue, Jazz Waltz, Rock, The Skip, The Morris Dance, The Schottische, Habanera, Paso Doble, The Sweet Pea, Samba, C & W, Tango, Fatback , Rumba, Bolero, Bossa Nova, Cha Cha, and Beguine.
Rhythm is constructed out of a time signature, a notation device that tells the musician how many beats are in one bar of music and what type of note constitutes a beat. The underlying rhythm or beat of a song is also called the pulse, and the speed of this pulse is what determines the tempo. These three aspects — the pulse, the time signature, and the tempo — are what create the initial and underlying rhythm for an entire song.
Western music typically uses a form of rhythm known as divisive: a rhythm in which a section of time is divided into tiny rhythmic units, usually one pulse. These rhythmic units vary depending on time signature and type. A metric rhythm is a steady pulse. An intrametric rhythm is slightly off the steady pulse, like some country-western or swing music. A contrametric rhythm is syncopated, and an extrametric rhythm is irregular, like triplets.
Percussionists generally get all the credit for a song’s rhythm, but rhythm is the province of every instrument and every musician. Understanding how notes relate to each other in a period of time is the concept of rhythm, and every musician must be familiar with it. Though the drums in a rock band or the piano in a jazz ensemble may be driving the underlying beat, all the musicians are playing a rhythm, and all rhythm is able to push a song forward.