What is etiquette?

The description of etiquette from the english dictionary says -

"conventional requirements as to social behaviour; proprieties of conduct as established in any class or community or for any occasion."

This basically means, that it is the expected standard of behaviour for a certain event or environment.

For example, at a Football (Soccor) match you are expected to cheer your team to encourage their success, singing and shouting from the start of the match.

  However, during Golf you are expected to stand quietly so you do not distract the Golfer. There is different etiquette for the different sports.

Etiquette is not normally explained by sporting events, it is usually linked with more formal events like weddings, formal dinners, funerals, however the principle remains, it is how you are expected to behave.  Here are some more examples of etiquette -

• Say hello when you see someone

  

• Use the outside cutlery first, and work your way in with each meal at a formal meal
• Don't talk with your mouth full
• Bow when you enter a Dojo

I suppose it is really an extension on good manners.  You are probably doing it everyday without realising it.