Etiquette is the code of unwritten expectations (which evolve into written rules) that governs social behavior. It usually reflects a theory of conduct that society or tradition has invested heavily in. Like "culture", it is a word that has gradually grown plural, especially in a multi-ethnic society with many clashing expectations. Thus, it is now possible to refer to "an etiquette" or "a culture", realizing that these may not be universal.
Etiquette fundamentally concerns the ways in which people interact with each other, and show their respect for other people by conforming to the norms of society. Etiquette instructs us to: greet friends and acquaintances with warmth and respect, refrain from insults and prying, offer hospitality equally and generously to our guests, wear clothing suited to the occasion, contribute to conversations without dominating them, offer a chair or a helping arm to those who need assistance, eat neatly and quietly, avoid disturbing others with loud music or unnecessary noise, follow the established rules of a club or legislature upon becoming a member, arrive promptly when expected, comfort the bereaved, and respond to invitations promptly.
Violations of etiquette, if severe, can cause hurt feelings, misunderstandings, or real grief and pain, and can even escalate into murderous rage. One can reasonably view etiquette as the minimal politics required to avoid major conflict in polite society, and as such, an important aspect of applied ethics. An etiquette can be considered to be an ethical code in itself.
The term etiquette, being of French origin and arising from practices at the court of Louis XIV, carries a strong whiff of anachronism, classism, and elitism, and it is common to disparage the entire field by setting it up as a straw man concerned only with "which fork to use". Because violations of rules of etiquette generally do not harm anybody, they are considered by some to be unnecessary restrictions of freedom. For instance, wearing pajamas to a wedding in a cathedral may be an expression of the guest's freedom, which may cause the bride and groom to wonder how the guest in pajamas feels about them and their wedding. Others feel that a single, basic code shared by all makes life simpler and more pleasant by removing many chances for misunderstandings.
The term is sometimes used synonymously with manners, though some writers make the distinction between manners to mean rules which involve justifiable respect shown to others, and etiquette to mean rules which are based purely on tradition and have little obvious purpose.
Etiquette is dependent on culture; what is excellent etiquette in one society may shock in another. It is a topic that has occupied writers and thinkers in all sophisticated societies for millennia, beginning with a behavior code by Ptahhotep, a vizier in ancient Egypt's Old Kingdom during the reign of the Fifth Dynasty king Djedkare Isesi (ca 2414-2375 B.C.). All known literate civilizations, including ancient Greece and Rome, developed rules for proper social conduct. Confucius included rules for eating and speaking along with his more philosophical sayings. Louis XIV himself wrote a book on court ceremony, and Benjamin Franklin and George Washington wrote codes of conduct for young gentleman. The immense popularity of advice columns and books by Miss Manners shows the currency of this topic.
The rise of the Internet has necessitated the adaptation of existing rules of conduct to create Netiquette, which governs the drafting of email, rules for participating in online forums, and so on.
A related term is kindness.