Passwords can be easily cracked by hackers, particularly if you don't use a strong password. A strong password is at least 12 characters or longer and comprises a mix of upper- and lower-case letters plus symbols and numbers. The shorter and less complex your password is, the easier it is for cybercriminals to crack. You should avoid choosing something obvious – such as sequential numbers (“1234”) or personal information that someone who knows you might guess, such as your date of birth or a pet’s name.