ruby - What does "+=" (plus equals) mean?

Question

I am doing some ruby exercises and it said I need to go back and rewrite the script with += shorthand notations.

This exercise deals primarily with learning new methods. The problem is, I have no idea what += means when I tried to look it up online.

Answer 1

+= is a shorthand operator.

someVar += otherVar

is the same as

someVar = someVar + otherVar