Parentheses are used to explain the statement or provide explanatory information in the sentence. This is usually to indicate a full interruption in thought.

To offset extra information

• CORRECT: I told Alistair that mozzarella was the most overrated cheese (which is putting it mildly).

Can be used to substitute for a word "or" in certain types of sentences.

• CORRECT: What part(s) are available?

Parentheses are also used in figure captions and with numbers of items in lists.

• CORRECT: Figure 1 shows two examples: (1) the handle orientation and (2) the frame structure.