If you forget your password, most Web sites will email it to you (assuming you can remember which email address you signed up with). The most secure method for remembering your passwords is to create a list of every Web site for which you have a password and next to each one write your login name and a clue that has meaning only for you. Just make sure you don’t store the information in plain sight.

I tend to agree with noted security experts Bruce Schneier, when he advises users not to worry about writing down passwords. My views on the advisability of keeping a written list of your passwords have evolved over time. Whatever you do, don’t store your list of passwords on your computer in plain text. Never use the password you’ve picked for your email account at any online site: If you do, and an e-commerce site you are registered at gets hacked, there’s a good chance someone will be reading your e-mail soon. It’s generally safe to re-use the same password at sites that do not store sensitive information about you (like a news Web site) provided you don’t use this same password at sites that are sensitive. Avoid using the same password at multiple Web sites. Just remember that each character you add to a password or passphrase makes it an order of magnitude harder to attack via brute-force methods. These days, it’s increasingly affordable to build extremely powerful and fast password cracking tools that can try tens of millions of possible password combinations per second. It used to be the case that picking an alphanumeric password that was 8-10 characters in length was a pretty good practice. Some of the easiest-to-remember passwords aren’t words at all but collections of words that form a phrase or sentence, perhaps the opening sentence to your favorite novel, or the opening line to a good joke. Avoid using simple adjacent keyboard combinations: For example, “qwerty” and “asdzxc” and “123456” are horrible passwords and that are trivial to crack. If you must use dictionary words, try adding a numeral to them, as well as punctuation at the beginning or end of the word (or both!). Password-cracking tools freely available online often come with dictionary lists that will try thousands of common names and passwords. Do not use words that can be found in the dictionary. Do not choose passwords based upon details that may not be as confidential as you’d expect, such as your birth date, your Social Security or phone number, or names of family members. Don’t use easily guessed passwords, such as “password” or “user.” Do not use your network username as your password.

Create unique passwords that that use a combination of words, numbers, symbols, and both upper- and lower-case letters. Take a moment to review these, and consider strengthening some of your passwords if they fall short. Here are a few tips for creating strong passwords.

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