Viruses are manmade. Even a simple virus is dangerous because it may use all available memory and bring the system to a halt. More dangerous viruses can delete or change the data on your hard drive. Viruses can be found and removed using antivirus software available at your local software store. I use McAfee, but Norton is good, too.
Email is a terrific way to stay in touch with family and friends, and to make new friends.
But some of your messages may be read by someone else. You see, as your message zips across the Internet to its destination, it passes through a bunch of other computers. Those computers might make a copy of your message and somebody may read it someday. When you send an email, pretend you're talking in a crowded room. There's no such thing as a private conversation on the Net.