In linguistics, a phatic expression is one whose only function is to perform a social task, as opposed to conveying information.1

For example: In English, "You're welcome" is not intended to convey the message that the hearer is actually welcome; it is a phatic response to being thanked, which in turn is a phatic whose function is to acknowledge the receipt of a benefit.2

Similarly, the question "how are you?" is usually an automatic component of a social encounter. Although there are times when "how are you?" is asked in a sincere, concerned manner and does in fact anticipate a detailed response regarding the respondent's present state, this needs to be pragmatically inferred from context and intonation.3