Possessive pronouns show that something belongs to someone. The possessive pronouns are my, our, your, his, her, its, and their. There's also an “independent” form of each of these pronouns: mine, ours, yours, his, hers, its, and theirs. Possessive pronouns are never spelled with apostrophes.

Is my a possessive pronoun or possessive adjective?

My, your, his and her are all possessive adjectives. We use a possessive adjective before a noun: This is my brother.

Is my a possessive case?

The possessive-case determiners are "my," "your," "his," "her," "its," "our," and "their." (The possessive determiners are known as possessive adjectives in traditional grammar.)