To make your passwords as strong as possible, don't use birthdays, addresses or phone numbers for example.  And change them regularly.  A strong password should be difficult (or impossible if you do a good enough job) for others to guess, and include eight or more letters and numbers.  To stay safe, don’t input your bank account details or confidential passwords on a shared computer at work.  Your PC will offer to remember your password, but think carefully about accepting that for important passwords like bank accounts.  If your PC remembers your password, anyone else who has access to your computer could use it too.  Managing multiple passwords is difficult, and writing them down is risky.  Remember anyone who finds a list of your passwords can use them too.  Finally, be sure that your computer is updated with anti-virus and anti-spyware protection.  Stealing your logins and passwords is common goal of spyware.