Most people use the internet for two main purposes.
1. To gather information, both factual and editorial, on subjects that they have an interest in or a need for.
2. To communicate with other people that have similar interest in topics they have an interest in, in order to exchange information on a one to one basic. This is done through instant message, emails, discussion forums and chat rooms.
Both of these purposes could also be fulfilled through offline activities and most people use both sources to meet their needs.
Then, there are people who use the internet to invade other people's personal space by purposely disrupting discussion forums or chat rooms. Some of these people go further by sending unwanted email and/or instant messages.
These people also typically engage in antisocial behavior just as name calling, threats and insults and also very typically braggadocio. They have found an outlet for pent up frustration and rage that they cannot legally and/or safely indulge in within offline settings. Every discussion forum on any subject matter has them.
I have seen them show up in as innocent a place as an online card playing community to wreak havoc by joining games, throwing a few insults and then moving on.
They are the vandals of the internet. Just as vandals invade other public places where people seek to enjoy their lives, they invade spaces on the internet as well.
Fortunately, they are easier to tune out on the internet an unlike graffiti vandals or those who in other ways defame the beauty of the world, their damage is less permanent here.
Joel