Braces: symbols used to connect more words or items that need to be considered together, equal or paired, or to enclose those items that only choose one item; One of a pair of symbols as a group in mathematics.

2. Square brackets "[]"

Brackets, also called square brackets, are often used in pairs. Parentheses are symbols used to connect words or items that need to be considered together, or symbols used to enclose items that only choose one from them.

3. Parentheses "()"

In parentheses, the symbol is (). It is both a mathematical operation symbol and a punctuation symbol. Function: explain the previous words; Supplementary explanation of relevant contents; Attach sequential words.