Search the web for sites to participate in chat discussions on all sorts of subjects. Do research for that school or work project. There is virtually endless amount of data out there. Play interactive games with real people on the other side of the world with out even leaving your home. Find cool places to go in your city.
Viruses are a serious threat.
Make sure that if you plan to surf the web, that you have an anti-virus program. DO NOT open any e-mails from people that you do not know. They may contain a virus. Also try to avoid downloading software from vendors that you are not comfortable with. Do research on them and find out their reputation.