Let’s learn about the eighth rest, also called the quaver rest (British).
First of all, a musical rest is a symbol used in music to represent silence. There are different types of rests, these include the quarter rest, half rest and whole rest.
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Each of these rests correspond with a particular note value. For instance a quarter rest has the same duration as a quarter note, a half rest has the same duration as a half note and a whole rest lasts as long as a whole note. While the note makes a sound, the rest is silent.
The combination of rests and notes makes music interesting. Without rests it would be boring. Imagine hearing a speaker go on and on without any pause between the words. 
In a 4/4 time signature, a whole rest lasts for four beats, a 1/2 rest for two beats, a 1/4 rest for one beat and an 1/8 rest for half a beat.
An eighth rest is half the length of a quarter rest. In other words two eighth rests make up a quarter rest, while four of them make up a half rest, and eight 1/8 notes make up a whole rest. 
How many beats an 8th note or rest gets will all depend on the time signature of the musical piece. In time signatures, the top number indicates how many beats in a measure while the bottom number indicates the kind of note that gets a beat. So while an 8th note gets half a beat in a 4/4 time signature, in a time signature with 8 at the bottom (for example 6/8), the 8th note gets one beat.
Counting Eighth Rests
When counting eighth notes or rests, count “1-and-2-and-3-and-4-and”. You must count every subdivision. Always count “and” on the second half of each beat to subdivide each beat by two.
Here are examples of eighth notes and rests and how to count them.
In the first example, count “1-and-2-and-3-and-4-and” and play an 1/8 note on each beat as well as its subdivision. In example two, play F note on beat 1 for one beat, rest on beat 2 for half a beat then play F on the “and”. Play quarter notes on beats 3 and 4. 
To draw a quaver, start just below the fourth line and draw a shape similar to the number seven.
The following diagram shows images of the various rests in music as well as their duration. 
Go here to learn more about eighth rests and piano notes.
Here’s a lesson about rests, note values and time signatures.
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