What do parentheses do in the Simple Query Syntax

The documentation for Simple Query Syntax says that

( and ) signify precedence.

What does this mean?

I've tried some queries with parentheses in them but I cannot figure out what they do. At first I thought it was like mathematical operators such that

+(term1 term2) = +term1 +term2

but that appears to not be the case.

Can someone provide an example where parentheses affect the query?

You can find the answer at the link below