For too many of us, passwords are annoying obstacles rather than valuable tools meant to keep our business (and back accounts) private. You may find yourself sticking with the same small number of passwords for every site, which means that you're only as secure as the least secure site you visit. Here are some tips to boost your online security:
Find out if your account has been compromised. Visit ShouldIChangeMyPassword.com to see if your account has been made public by hackers. You only need to enter the e-mail addresses used on your accounts, and of course there are still plenty of compromised accounts that remain unpublished, but this is a great starting point.
Change your passwords. Even if none of your accounts show up here, you may want to take a half-hour to change the passwords on your most important sites, then set up a reminder to do so every few months. Picking a memorable password is easy, but picking a strong password can be tough. Here's a great overview of how to check your passwords' strength.
Use a password generator. Password Hasher is a great, simple tool for generating strong passwords with Chrome and Firefox extensions, but it does require a master password, so while it adds a new layer of security, a dedicated hacker may still be able to sneak past it. The Wolfram Alpha knowledge engine can also help you generate strong passwords--just type "strong password" or something similar into the search box and see what comes up. There are plenty of options to tweak, so explore and see what works for you.
The system is only as secure as you make it. This means that if you set up an unrealistic system for yourself (like changing your password every day), you may end up less secure than if you pick a schedule or a tool you know you can work with. If you're going to go with Password Hasher and switch twice per year, that's far better than just crossing your fingers and hoping for the best.