What's Music?

Music, put simply, is the language of musicians. It gives them a way to communicate what pitches to play, how long to play them for, and how loudly they should be played.

If we didn't have music, all of our songs would just sound like noise.

Once you finish reading this section, you'll be equipped with all the information you need to explore Compose-away and Performance Alley.
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Written music contains several different notations telling you about how to play sounds.

A typical staff looks like this:

There are five lines and four spaces:

A clef is added to the staff based on the relative highness or lowness of the notes.

The staff is divided further into chunks called "measures" (or "bars"). Measures simplify the reading of music.

What goes inside measures? You guessed it, NOTES!

The place and style a note is drawn in tells you about its pitch and duration. Here are some of the most common notes you'll encounter:

As you can probably tell, music and math are very much connected. If you're a strong math student, this should make lots of sense.

In order to know how many notes should be in a measure, we can look at the time signature.
- This measure has 3 quarter notes ("4" means quarter note) per measure.


Tempo defines the speed of a piece of music. It sets a steady beat that repeats for the duration of the piece. Some music can sound completely different if played with the wrong tempo. You can experiment with tempo in Compose-away.


Rhythm describes the times in music when there is sound and the times when there isn't (notes and rests). When put together, this forms a pattern that can be reused throughout the piece. Frequently, however, many different rhythms are used.


Notes are organized into an alphabet, but it only extends from A-G, then loops back to A.

The Performance Alley keyboard is a great way to learn more about pitches.


Harmony is a way of adding texture to a musical piece.

Additional notes are played behind the melody to support it and help illustrate a mood.

Another type of harmony is when multiple voices are playing. Try out the "Canoe Song" in Performance Alley. Where you see stacked notes, try playing just the bottom ones, and then repeat, playing just the top ones. Notice that the song doesn't sound as rich. But when you play them both together, it sounds pretty cool!


In real-life orchestras or bands, music has to be arranged into many parts to be played by different instruments. We've kept things simple here since we're dealing with basics.

Now It's Your Turn!

There are two interactive activities that you can play with for as long as you want.