Personal pronouns are words that replace specific nouns in a sentence, making communication clearer and more efficient. They refer to people or things and can indicate the speaker, the listener, or others. Common personal pronouns include I, you, he, she, it, we, and they. These pronouns change form based on their role in a sentence. For example, I is used as the subject, while me is used as the object. Understanding personal pronouns helps in constructing sentences that are grammatically correct and easy to understand, enhancing overall communication.