Parentheses are usually used to set off material that is not essential to the main sentence. Such interruptions should be minimized.
If the material within the parentheses is part of a larger sentence, terminal punctuation goes outside the closing parenthesis (as in this case) .
If the parentheses enclose one or more complete sentences, then all punctuation stays inside the closing parenthesis. (Final punctuation here goes inside the parenthesis . )
To include parenthetical information within a clause already inside parentheses, use square brackets (such as shown here [square brackets]) or a dash (such as shown here—a dash).
Also use square brackets in a direct quote around words that have been altered or inserted.
“He said this” might be changed to “[John] said this.”