Many free and subscription Web sites require you to register before using their services. This usually requires three basic things: an active e-mail address, a username and a password.
Aside from the security risks of giving your e-mail address and other personally identifiable information to a random Web site, a lot of people simply don't want every Web site they visit to know who they are, and certainly not how to contact them.
For security purposes, experts recommend that you don't use the same username and password to access all of your Web sites and services. The danger, of course, is that one of these sites will -- either maliciously or accidentally -- hand your information over to identity thieves who will use your universal username and password to access your online bank account or other highly sensitive Web services.
Another annoyance is that many Web sites have no problem with selling your information to third parties who will then load your inbox with spam. Some sites allow you to opt out of receiving e-mails from partners, but it isn't always clear which boxes to check or uncheck.
If you don't want to give your real e-mail address to every Web site that requires registration, you can always create multiple e-mail accounts using free services like Yahoo! Mail or Google Mail. For most Web sites, the only real purpose of the e-mail address is to confirm registration, so it's OK if you never check the e-mail account again.
However, if you register with many different Web sites and want to keep track of all of your different usernames, passwords and e-mail addresses, don't create an Excel or Word file and save it on your computer. If someone is able to access that file, they'd have more than enough information to steal your identity.
A better solution is to use a secure, Web-based service like ShopShield or Anonymizer. These services automatically generate temporary e-mail addresses with unique usernames and passwords for any site you wish. Whenever a new e-mail message is received at one of these temporary accounts, it is scrubbed for viruses and spam and then forwarded to your real e-mail address. You can also delete unwanted accounts with a click of a button.
Another clever solution is a Web site called BugMeNot.com, in which users post free usernames and passwords for shared access to popular Web sites like newspapers and video sharing sites. If a username and password stops working, it is voted down the list.
For lots more information about online privacy and the mechanics of the Internet, follow the links on the next page.