5. Do not respond to or click on links in emails that look exactly like email from your bank, credit card company, retail stores, insurance companies, etc.. This is called phishing. Phishing is the act of sending an email to a user falsely claiming to be a legitimate enterprise.
This is an attempt to scam the user into surrendering private information that will be used for identity theft. The email directs the user to visit a web site where they are asked to update personal information, such as passwords and credit card, social security, and bank account numbers, that the legitimate organization already has. The web site is bogus and set up only to steal the user's information.
Once you visit their site, they'll try to get private data from you, like passwords. These web sites can look identical to your own trusted sites. If you really wish to visit the site shown, type it in the address bar of your web browser by hand. When in doubt, call the institution on the phone.
For more security information visit Seniors Guide to Computers.