Nobody is going to read your post and say "He violated rule 25! To plonk with him!" — but if you violate a rule because you don't know what it is, the reader is likely to feel, without quite knowing why, that you are rude, or stupid, or just not worth bothering with. If you violate a rule because you know what it is, you'll have a much better chance of getting away with it.
When you enter a forum for the first time, be a little diffident, and don't post until you are sure you know what the rules are — or, at least, post only in response to posts from people who are definitely not intruders, and who have asked a question that you can answer from personal experience or unusual expertise. It would be wise to mention your special qualifications — NOT puffing up and saying "I'm an expert, everyone bow down and worship my expertise", but more along the lines of "It appeared to be in good shape when I saw it last week".
(Digression on expertise: be very, very cautious in bragging about your knowledge. If you happen to high-hat it over the premier expert in the field you've claimed superior knowledge of — and you don't even recognize the name — you'll never live it down. It is even more dangerous to let your theoretical knowledge make you condescend to people with practical experience.)
It's fashionable to decry shibboleths, and call people dirty names such as "elitist" and "exclusionary" for using shibboleths to keep people out, but bear in mind that the original purpose of asking people to say "shibboleth" was to keep out spies who intended to murder you in your bed. Intruders on the Net won't kill you — but they might very well kill your forum.
And it's silly to call a club "exclusive" for having a password when they post the password on the door!
When people say "People on this group are offended when you call their passion 'sci fi'.", what they are really saying (though it's rare that they *know* they are saying it) is: "Are you a person who intends to behave himself and play nicely, or do you enjoy offending people?" This has become, alas, a necessary precaution.
Shibboleths tend to be less common when discussion is more specialized: you don't need a password to tell a person who wants to learn how to backstitch a seam from a person who wants to derail the conversation.
On the other hand, groups that are perceived as appealing to women are attractive to perverts. If you post to a needlework group with a query about, for example, fitting humongous boobs, it's wise for a newcomer to present the query with a certain amount of hesitation even if you've just read a long thread about quick-release fasteners for strip-tease costumes. (Come to think of it, especially when there has just been a long thread about strip-tease costumes.)
On the third hand, males in needlework groups are particularly welcome, because people who enjoy a craft think it a great pity that anyone should miss out. Even a group with "Women" in the name is apt to have several highly-valued male contributors. If you didn't have to prove you were female to get in, don't address the group as "ladies".
Gratuitous tangent: I've recently learned why Web sites often require a sign-in even when they have no use for the information: there's a library on the Web where all books are free for download, and books in bunches are available on CD for little more than shipping and handling. (http://www.handweaving.net/DAHome.aspx) When people complained about having to sign in to use the library, the librarian explained that there are bots which crawl the Web and download entire websites — Google, for example, does this as part of its indexing. There is so much information on the website that it costs four hundred dollars in connection charges every time a bot does that! It is, therefore, necessary to limit access to humans.
But even when quoting is not required, it may be well to indicate which part of a long post you are talking about.
When you quote, there are three common ways of doing it:
Top posting is the practice of writing your response, then appending the entire thread to date below your signature. Top posting is often the rule in business correspondence — it puts the entire transaction in one document, but the recipient needn't notice the appended history unless he has forgotten something. In business correspondence, top posting replaces the former custom of beginning a letter by giving the date of the letter to which you are responding so the reader can find the carbon copy in his files.
Bottom posting is the practice of quoting the entire thread to date, then writing your comments at the bottom. Bottom posting is the rule in some help forums, as it allows a would-be advisor to find all the details of the problem and all of the attempted solutions without backtracking into the archives.
Bottom posting keeps the messages in the order in which they were written, which makes them easier to read when you want to read all of them. This does require you to page all the way to the bottom to find the new material — but it also allows you to read only the latest post in the thread.
Quote and Response is the default rule in situations where each post has to make sense on its own. In asynchronous forums such as newsgroups, it isn't uncommon for a reply to arrive before the post that it is a response to. In mailing lists, one should assume that the reader has already deleted the message that you are answering.
Quote and Response means that you quote only the part that you are responding to, and type your response under the quote. If you are responding to several points, you quote each point separately and put its response under it.
You don't have to quote, unless the exact wording of the original post is important. For example, instead of saying
=================
John said:
> Thimbles are important
but needles are more important.
=================
you could say:
=================
I agree that thimbles are important, but needles are
more important.
=================
Remember at all times: the purpose of quoting is to make your post make sense. Don't quote irrelevant material and make the reader try to figure out what it has to do with your remarks. If your post makes sense without reference to what has gone before, don't quote. If your post doesn't make sense, make it make sense.
Clearly mark which words are yours and which are part of the quote. Put a blank line after the quote to make sure that the first line of your response doesn't get appliquéd onto it.
There are several ways to label quotes. The most common is to put a special character to the left of each line of the quote, and the most-common special character is ">". Many reading programs will also color lines that begin with a special character, usually blue, but this is selectable in some programs — at the reading end, not the writing end.
Lines that begin with words that are spelled ">word" instead of "word" are hard to read. Putting a space or two after the special character turns this into an indented passage with a line of marks in the margin, which is much easier to read. If your program doesn't put this space in automatically, go through and do it by hand. (But poke around in the menus: if you can select the special character, you can select "> " or "> ".)
If the quote is so long that it's a chore to put the spaces in by hand, consider whether you need that many lines of quote. If you need all of them, consider whether there is some other way to mark it as a quote. You can draw a line above and below it, indent and single-space it, write "Begin quote . . . end quote", or whatever seems appropriate to the medium you are posting in.
Most readers get trained to skip quotes, and go back to them only when it becomes apparent that they don't remember enough of the previous post. A reader who opens a message that is all quotes is likely to conclude that someone hit "send" by mistake, and go on to the next message. So if you are pasting in a lengthy message for some reason, don't use the mark-on-every-line quote marks, but one of the alternatives in the above paragraph. If, for example, you are forwarding a message for someone who can't post directly at the moment, don't paste as quote, just write a brief introduction that ends in a colon, and put in a couple of blank lines. If that doesn't feel like enough, there are several characters that can be used to draw a line across the screen.
URLs also require a little clothing. Posting a naked URL is a favorite trick of spammers; people aren't likely to click on a link unless you give some hint as to why you posted it. And "This is really funny!" won't do; that too is a favorite trick of spammers, particularly those that get their kicks by disgusting people.
It is rude to give a URL instead of an answer without stating why you can't simply post the answer.
It's also rude to mention a Web page without giving the URL to allow the reader to look at it for himself — or saying that you remember the site but not the URL, or that you have some other reason for not mentioning the URL.
Unless, of course, the forum is a game to find Web sites on cryptic clues. See Rule #1.
Well, and whether it's suitable for the forum in question. You are no doubt thinking "dirty" or "offensive" — but there are also in-jokes that most of the people on the forum can't be expected to understand. And on some forums (see Rule #1), clean jokes are offensive.
Think twice, post once. And the more posts you have already contributed today, the more hesitant you should be about sending yet another.
How many is too many? (All together now) SEE RULE #1! As a rule of thumb, the more posts other people contribute, the more you can send without overwhelming the group. But I once belonged to a very busy mailing list that had a rule against posting more often than once a week, in the vain hope of keeping traffic down to a level that didn't flood mailboxes with more messages than the members had time to delete unread.
If there are two or three paragraphs visible when the reader first sees your remarks, you have two or three chances to catch his attention: if the first line of the first paragraph doesn't grab him, he's likely to glance at the first line of the second paragraph to see whether things get better. If there isn't a second paragraph to glance at, he's outta there.
The question of *where* to put your paragraph breaks is way beyond the scope of a simple set of rules, but I've a word on *how*: hit "enter" twice.
On paper and in other media, there are many ways to separate paragraphs, but in plain text blank lines are the only method that will stick. A single return gets lost among those that are added to wrap the text to fit the screen, and indents may run afoul of software that removes excess spaces. (Not to mention that indents don't show all that much in some displays.)