Speech acts are utterances that serve a communicative function, such as apologies, greetings, requests, complaints, invitations, compliments, and refusals. There are three types of speech acts: locutionary acts involve just saying something, illocutionary acts perform an action through an utterance like requesting or warning, and perlocutionary acts seek to influence the feelings, thoughts, or actions of the listener like persuading or inspiring. Indirect speech acts use utterance forms associated with one function, like a question, to perform a different function, like a request. They are considered more polite in many societies than direct speech acts.