Why is security important?

There are two reasons why security should be an important item for everyone.

Personal Protection of Information: If you store any data that you would not like publically broadcast to the world it is in your interest to provide a level of security which protects that information.
Social Responsibility: By connecting your machine to the residence hall network you have become a member of several communites. The residence hall network, the campus network, and the global network. As such you have a social responsibility (though one you can choose to not fullfill) to protect the groups well being. A good reason for an intruder to gain access to a res-hall machine is to use it as a launching platform to attack other machines. It is very common for network intruders to take control of sever machines like this and route their traffic through them in order to make a trace back more difficult.