Changing your online passwords periodically (at least a few times a year) is good practice, as is choosing secure passwords. One technique for creating an easy to remember, but hard to guess password is to base it on a quote. For example, “Lmn2tmotm” is an acronym based on Shakespeare’s Sonnet 116: “Let me not to the marriage of true minds.”

Whether you are a college student or a traveling business person, keeping your laptop physically safe is an important part of computer security. Leo Notenboom, of Ask-Leo.com, recommends encrypting your data. Microsoft has additional tips on laptop security.

While traveling, public computers at cyber cafes, hotels and libraries can be convenient. But they also can be dangerous. In addition to making sure that your passwords are not saved in browser history, you also have to be concerned about keyword loggers that may be watching your every keystroke, and emailing your passwords to a thief. Although the safest route would be to never use an important password on a public machine, the next best thing to do is to be sure to change all passwords you used on the road when you return to a secure computer. For more, read “5 Safety Tips for Using a Public Computer.”

A firewall is your protection against Internet bad guys that want inside your computer. Firewalls are often included in routers and other Internet hardware, but for a single machine, a software firewall is sufficient. Two recommended products are Zone Alarm (free for personal use and Norton Personal Firewall. For more reviews, read
Firewall Guide.

Ever wonder why so many websites ask you to enter squiggly, distorted pass codes? They are using captcha to verify your humanity. A captcha is an automated test that humans can pass, but computers can not. To learn more, read the definitions from Webopedia or Wikipedia. Or dive into Carnegie Mellon’s Captcha Project.

When spyware takes control of your browser by changing the start page and the default search engine, it is called a browser hijacking. To thwart most hijacking attempts, many experts advocate using Mozilla Firefox instead of Internet Explorer. If you are already are infected, HiJack This is a free tool that will list all your browser plug-ins. Learn more browser hijacking at Spyware.info.

As more and more sites require registration with a username and password, it becomes increasingly important to manage your passwords. One way is a paper address book. Another is a software password vault. My favorite password saver is Roboform. When evaluating a password program, be sure to consider how you will access your passwords when you are away from your primary computer. Roboform allows backup to a Palm PDA or a USB thumbdrives.

Although many legitimate college scholarships exist, the FTC warns students and parents not to fall for any of these six scams. “The scholarship is guaranteed or your money back.” “You can’t get this information anywhere else.” “I just need your credit card or bank account number to hold this scholarship.” “We’ll do all the work.” “The scholarship will cost some money.” “You’ve been selected by a ‘national foundation’ to receive a scholarship.” “You’re a finalist” in a contest you never entered. Learn more at the FTC’s $cholarship $cams website.

Phishing (also known as carding or brand spoofing) is a type of e-mail fraud that tries to get you to divulge sensitive financial information such as a credit card number or account password. To learn more, read this definition from Webopedia ( http://www.pcwebopaedia.com/TERM/P/phishing.html ) and this alert from the Federal Trade Commission ( http://www.ftc.gov/bcp/conline/pubs/alerts/phishingalrt.htm ).

A firewall is a piece of software or hardware that monitors incoming Internet traffic and allows only trusted connections. Whether you have an always-on Internet connection (such as cable) or use dial-up, a personal firewall is necessary for online safety. For product reviews and specifics, try PC Magazine or PC World .