People and companies use E-mail to send messages to thousands of people at a time, encouraging them to buy something or visit a web site. The process, known as “spamming,” can be intrusive and annoying. Some use spamming to try to entice people to visit sexually explicit web sites.

Each E-mail message you send and receive contains a return address. Many people don’t realize the return address can be fake. So, just because you get a message from “grandma@cottage.com” doesn’t mean it’s really from grandma. It may really be from wolf@bigfangs.com.

E-mail also contains a “header.” Headers provide more information about who sent the message and where it came from. Understanding the header information can be difficult, but if you ever receive an E-mail message that doesn’t make sense; is threatening; or contains things that make you feel scared, uncomfortable, or confused, you should report it to your Internet service provider and ask them to investigate where it came from. You can easily find that address on the service’s main web page (www.servicename.com). When in doubt report the message to webmaster@servicename.com (substitute the name of your service for “servicename.”)

If you think any information you receive is illegal, you should report it to the CyberTipline® at www.cybertipline.com or call 1-800-843-5678. Illegal material includes threats to your life or safety, threats to others, pornographic images of children, and evidence of other crimes. NCMEC will refer this report to the appropriate law-enforcement agency.

Be careful about replying to E-mail from people you don’t know. Remember, the sender may not be who he or she seems to be. By replying you are verifying a valid E-mail address to the sender, and that information can be used to encourage a person who may send inappropriate messages or put you on even more E-mail lists. Never send a photograph of yourself or any personal information to someone you don’t know.

E-mail can easily be copied and forwarded to others. So if you do send personal information to friends, be sure they will respect your privacy.

• Anyone you don't know who asks you for personal information, photos or videos.
• Unsolicited obscene material from people or companies you don't know.
• Misleading URLs on the Internet that point you to sites containing harmful materials rather than what you were looking for.
• Anyone who wants to send you photos or videos containing obscene content of individuals 18 and younger. (The possession, manufacturing, or distributing of child pornography is illegal.)
• Online enticement for offline sexual activities. (No one should be making sexual invitations to you online – and it’s an especially serious crime for adults to do it.)