A user who had previously double posted is reprimanded for triple posting later on. This image has an uncertain copyright status and is pending deletion.

Multiple posts

One common faux pas on internet forums is double posting, where a user posts a message twice to the same forum. It can also refer to people posting versions of the same post that are only slightly different, especially in forums where they are allowed to edit their earlier posts. In that case, double posting in lieu of editing prior posts can artificially inflate a user's post count. Double posting can be accidental, as when the user sees an error message while their browser submits the HTTP POST command even though the message is still transmitted, when the user of a slow forum grows impatient and repeatedly hits the submit button, or, in more agreivous cases, double posting can be used as a method of trolling or spreading forum spam.

Related problems, such as crossposting, occur when the user posts the same post to multiple forums. This problem was inherited from Usenet, and is a common complaint in many forums.
A so-called spam-board, where administrators and moderators allow spam subjects and posts in order to quickly enhance their forum in size, but not quality.

Spamming

Forum spamming is a breach of netiquette where users repeat the same word or phrase over and over again, but is different to double-posting in the respect that spamming is usually a willful act which sometimes has malicious intent. This is a common trolling technique. It can also be traditional spam, unpaid advertisements that are in breach of the forum's rules.

Trolls

A troll is a user that repeatedly and intentionally breaches netiquette, often intentionally posting derogatory or otherwise inflammatory messages about sensitive topics in an established online community to bait users into responding. They may also plant images and data on networks that others may find disturbing in order to cause confrontation, such as links to goatse.cx. While not related to hacking, trolling could be interpreted as banned by the American Computer Misuse act of 1990, where the intent of such mischief is to cause chaos is spread.

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