The bottom number shows the note value, and the top number tells us how many will be in a measure.
Understanding what a time signature is will be important if you want to understand 6/8 time, so read our guide on time signatures if you’d like to dive into some more detail.
6/8 time vs. other time signatures
The grouping of the 6/8 time signature sets it apart from others like 3/4 or 4/4.
The 6/8 time signature is a “compound meter”, meaning that its beats are subdivided into groups of three. The “6” in the time signature tells us that there are six beats per measure, while the “8” shows that the eighth note is the note value we are referring to. This gives the time signature its rolling or lilting feel.
Some people get confused between 6/8 and 3/4, wondering if they are the same time signature. If you’re one of those people, don’t worry. It’s a common problem. But it’s not hard to wrap your head around.
Perhaps the confusion lies in the fact that three quarter notes and six eighth notes are, mathematically speaking, the same thing. But the difference is in the way that they are grouped together.
3/4 is grouped as one set of three quarter notes per measure, which gives it a “one-two-three” waltz-like feel. On the other hand, 6/8 consists of two sets of three eighth notes per measure (or two dotted quarter notes). That’s why we call it a “compound meter”. This difference in beat grouping is what distinguishes the two, and it affects the way the two time signatures sound different.
If you want to understand the difference in more depth, check out this video: