Netiquette is a “set of rules” or maybe “a guide” to behav correctly in forums, wikis, mailing lists, etc. in all Internet communication ways.
For example, is a well known rule on Internet, writing in small letters, don’t use capital letters, because this last ones mean that the user is screaming.
Other common rules are search first you put a question in any forum, mailing list, etc. is important don’t repeat topics that previously were answered so, search first is the first thing that you must do when you get a problem.
Other typical situation in blog is to indetify “trolls”, trolls are people who damage the environment of the site creating duscussions, insulting, etc.
In the part of behavior, I read somoe days ago regarding this, the treatment to old members, if something common that old members (administrators or others) are behaving like “gods” maybe not always of course, but for these reason you have to try talk with them like other members with less experience in the forum, with respect, but don’t with afraid.
Other point that I liked very much when I’ve read news about this, is the neccesity of explain your answer when you get it, I mean, when you write a question in a forum, you expect that other members give you support and helping you, but sometimes, there isn’t any help, so maybe, later, you find your own answer, ok, but then, you don’t must forget to write the answer in your open post that you wrote your own question!! not is accepted only the typical “I find, thank you!” NOOOO!!! Write the answer, explain how do you do, etc. is likely that other person has your own problem, and if you aksed before and gave your answer this new person will have the question/answer in an easy way.
In conclussion, netiquette is like rules of behavior, but not special rules or strange, these rules are based on the good behavior on a usual community of people, like your friends, classmates, family, etc.
More info at Netiquette RFC.
See you my friends!!!