Repeat bars are used to repeat a segment of the score:
On this staff (stave ), there are two repeat signs, it works like mirrors. The first measure (bar ) is played, nothing special.
The 2nd measure is played normally, but you will have to memorize the location of the repeat sign, here it is simple because the staff has only one line.
The 3rd measure is played normally.
The 4th measure is played normally.
After you have fully played the 4th measure, the repeat sign indicates that you should go back to the previous repeat sign.
The 2nd measure is played again.
The 3rd measure is played again.
The 4th measure is played again.
Mission accomplished! We played the passage between the two repet signs, we can continue our way.
Final bars (Final barlines )
Final bars are used to indicate the end of the score
Double bars (Double barlines )
Thin double bars and dotted bars are used to indicate a change (of key signature for example) or something special