The violin has many things in common with the viola, which is why it's sometimes hard to tell the difference! The violin has 4 strings, and uses a bow to play them. It also has the same shape and size as the viola! But the violin is different to the viola, it plays slightly higher notes than the viola and is slightly smaller in size. 

The viola is very similar to the violin. It can play lower notes than a violin and is also slightly bigger in size. The viola has 4 strings, which make the sound of each note when the 'bow' is moved over each string. To play the viola you need a 'bow' which is in the picture below. 

 The cello looks like the violin. Doesn't it? Well actually it's much larger! It's actually the 2nd biggest string instrument in an orchestra! You may also notice that there is a 'leg' coming out from the bottom. This is used to bring the strings up to the player, so he/she doesnt have to bend down to play the cello. It also uses a bow to play the notes!

The double bass is the largest of the string instruments. It also has 4 strings, and uses a bow to play them. The double bass plays the lowest notes out of all the string instruments! The double bass is very large in size! It also has a 'leg' at the bottom, although you may not need it as much as the cello!

The piano may not look like any of the other string instruments, and you may be wondering why it's in the strings section? Well inside a piano is actually steel strings! The keys which you press, move a little hammer which hits a string! This is what causes the noise! Do you remember from the book which hand you play the bass and treble clef with? You play the bass clef with your left and the treble clef with your right hand! Well done!