Sometimes called square brackets, are most often used to show that words have been added to a direct quotation.
Sometimes, when quoting a person or document, adding a word or two is necessary to provide enough context for the quote to make sense.
Examples:
To add further information to the above it can be written as:
Examples:
Periods, question marks, and exclamation points should be paced in the parenthesis or bracket only if they belong to the words inside the parentheses or brackets. If the punctuation belongs to the surrounding sentence, put them outside the parentheses or brackets.
Never put a comma immediately before a closing parenthesis
Examples: