Western music notation is a graph of pitch (on the vertical axis) and time (on the horizontal axis.) It’s mostly self-explanatory on the pitch axis, but it’s harder to understand on the time axis. It helps if you visualize your rhythms on a circle, like the Groove Pizza does. Everything I talk about in this post will assume that we’re in 4/4 time, because it’s the default rhythmic setting for Western music, and all note values are determined in reference to it. Also, 4/4 is the time signature of most of the music that you probably like.
The simplest rhythmic value is the whole note. This is a note that lasts the entire duration of a measure of 4/4. If you sing a note that lasts for one lap around the Groove Pizza, you’re singing a whole note.
If you divide the measure in half, you get half notes. You can sing half notes by starting your notes when the Groove Pizza is at twelve o’clock and six o’clock.
If you divide the measure into quarters, you get quarter notes. (Who said this was hard?) Quarter notes are special in 4/4 time, because beats are one quarter note long. If you count “one, two, three, four” along with the beat of any pop or rock song, you’re counting on the quarter notes. As you count, make sure to clap on the backbeats (three o’clock and nine o’clock on the Groove Pizza.)
The diagram above introduces a new symbol, the one at the three quarters position. The dot means “multiply my normal length by one and a half.” So, a dotted half note is the same thing as a combined half note and quarter note.
Dividing a measure into eighths gives you eighth notes. The little flag on the note stem means that it’s half as long as a quarter note.
There’s another new symbol in the diagram above, a tie that combines two notes together. There is no standard symbol for a note that’s 5/8 of a measure long, so you need to tie a half note and an eighth note together. To make a note that’s 7/8 of a measure long, you tie a half note with a dotted eighth note.
If you divide the measure into sixteenths, you get sixteenth notes. The double flag on the note stem means that it’s half as long as an eighth note.
For even finer subdivisions of the measure, you just keep adding flags: three for thirty-second notes, four for sixty-fourth notes, and so on. When you write strings of eighth or sixteenth or thirty-second notes, their flags merge together into beams, like in my little song below.
I haven’t yet talked about rests. For every note value, there’s a corresponding rest, a silence when you don’t play or sing. In my silly note values song, the top staff has all the note values, and the bottom staff has rests of the same lengths.
At this point, you might be wondering: what if I want to write in a time signature other than 4/4? The confusing thing is that no matter what time signature you use, the note values still refer to fractions of a measure of 4/4. So, if you’re writing in 3/4, a quarter note won’t be 3/4 of a beat (a quarter of three beats) long, it’ll still be one beat (a quarter of four beats) long. If you’re writing in 5/4, a whole note won’t be five beats long, it’ll still be four beats. This takes some getting used to, but I guess the advantage is that you don’t need to learn a bunch of new symbolic meanings for every time signature.
You may also be wondering, what if I want to divide up the measure by some factor other than two? What if I want to subdivide by threes, or fives, or sevens? In that case, you need to use tuplets, and those are beyond the scope of this post.