In sociology, manners are the unenforced standards of conduct which show the actor to be cultured, polite, and refined. They are like laws in that they codify or set a standard for human behavior, but they are unlike laws in that there is no formal system for punishing transgressions. They are a kind of norm. What is considered "mannerly" is highly susceptible to change with time, geographical location, social stratum, occasion, and other factors. That manners matter is evinced by the fact that large books have been written on the subject, advice columns frequently deal with questions of mannerly behavior, and that schools have existed for the sole purpose of teaching manners.

A lady is a term frequently used for a woman who follows proper manners; the term gentleman is used as a male counterpart.

The body of behaviors we call "manners" are evolution's solution to easing the stresses of communal living. In essence, mannerly behavior recognizes the right of another to share the communal space. Many of our daily expressions of politeness reflect this function. Saying "excuse me," for example, shows that you recognize that you have invaded another's space, and regret the necessity of doing so. It is a basic tenet in law that it is wrongful to cause damages to another (see norm). Since there cannot be a law for every slight, daily causing of damage to another, manners serve to at least acknowledge, if not make recompense, for the damage.

Miss Manners regrets that in recent times the idea that one should be "assertive" has gained currency, holding that being assertive is simply another name for "the Impulse Rude," which is to be resisted at all times. She prefers "the withering look, the insistent and repeated request, the cold voice, the report up the chain of command, and the tilted nose." She also rejects the idea that manners is all about making people comfortable, "as if etiquette weren't magnificently capable of being used to make others feel uncomfortable," all in the name of preserving peace in the public arena.