by Christopher Null, PC World

What's okay on Facebook? On sites like MySpace, anything goes (or seems to), but the rules of etiquette on Facebook seem to be a little more refined-not a lot, mind you, but a little. Keep these tips in mind, whether you're making your first friend or your 1000th.

Consider how many friends you really want

Some people adopt an everyone-welcome policy on Facebook and accept all friend requests; some only want real-world contacts in their friends list. In deciding on the right approach for you, bear in mind that the bigger your friend network is, the more application, event, chat session, and cause invitations you'll receive-and that can lead to some uncomfortable moments and the occasional friend purge.

Go easy on the updates

As on Twitter, oversharing on Facebook can be a problem. Every meal eaten, every TV show experienced, and every weather condition observed need not be the subject of a status update. Ask yourself whether anyone is likely to care about your comment before you start typing.

Keep quizzes to yourself

It's fine if you want to take a "Which serial killer are you?" quiz. When you complete all of the multiple-choice questions, however, you'll almost certainly be asked to invite a dozen or so people to take the quiz, too; there's no need for this unless you think they'll really enjoy it. Look for a 'Skip this step' or 'Continue to result' button (in tiny type) somewhere on the page, click it, and you won't have to send invitations to anyone as a precondition to getting your quiz results. Clicking the 'Skip' button on the following screen will prevent the quiz from showing up on your wall or being shared on your friends' walls.

Limit Facebook chat

Just because someone has a Facebook window open doesn't mean they're automatically available for a chat session. Facebook Chat is like any other instant messaging platform-use it appropriately, and recognize that your friends may be too busy to respond immediately, especially during business hours.

No poking

If you are over the age of 16, don't "poke" people-seriously.

Avoid "Group think"

One disconcerting trend among many Facebook users involves creating a Group for a business concern, and then inviting everyone under the sun to join the group. This is a misuse of the feature-and bad manners-since Groups are designed to serve as gathering places to discuss genuine leisure, cultural, social, or other common interests, not as ad hoc copy shops.

Common courtesy should impel you not to create a Group for your business-but if you insist on doing so anyway, please invite only employees to join the Group. If your business needs a Facebook presence, create an official Page for it; then, if you must, invite friends to becomes fans of that Page.

Think before posting embarrassing photos

Resist the temptation to post every last photo from your birthday party on Facebook, particularly images that may cast your guests in an unflattering light. If you have any doubt, ask the subjects of any iffy pics in advance whether they'd mind your posting the shots; then abide by their wishes.

Tag lightly

The same thing goes for tagging: The people in a picture might not object to its being online as long as their names are not associated with it.

Untag as you please

It is no breach of etiquette to untag yourself from any photograph. Remember, though, that untagging is permanent: You can't be retagged to a photo once the tag is removed.

Feel free to ignore requests

You are under no obligation to acknowledge a Facebook friend request, whether it comes from a stranger or from someone you know but don't want as part of your digital life. After all, you wouldn't be obliged to seat visitors at your dinner table if they showed up without warning at your house at 7 o'clock. (One alternative way of dealing with this situation is to add iffy contacts to a severely restricted limited profile list.) On the flipside, if you want to friend a stranger (for whatever reason), add a note of explanation to your friend request, explaining who you are and the reason for your request.