The speech act is a concept in linguistics and the philosophy of language. It can be described as "in saying something, we do something", such as when a minister says, "I now pronounce you husband and wife", or an action performed by means of language, such as describing something ("It is snowing"), asking a question ("Is it snowing?"), making a request or giving an order ("Could you pass the salt?", "Drop your weapon or I'll shoot you!"), or making a promise ("I promise I'll give it back"). Other common examples of speech acts include greeting, apologizing or insulting.
Examples
"watch out, the ground is slippery" → warning
"I will try my best to be at home for dinner" → promising
"Ladies and gentlemen, may I have your attention, please?" → requesting
"Can you race with me to that building over there?" → challenging