Creating an endlessly difficult password According to iFusion Labs' estimations, a seven-character password made up of just lowercase letters might be broken in around two hours and twenty minutes. But a similar password containing both upper- and lowercase letters would take more than one hundred years to break! A number-based password could never be cracked using conventional means because there are too many possible combinations. A password is considered impossible to crack if no computer can solve it within a reasonable amount of time. Preventing passwords being cracked If you can't come up with a good password, there are tools available that will generate them for you. These include Password Generators such as the popular MyPasswordManager (free) which will create random characters and put them into a list for you to choose from. Of course, using these types of tools makes your password space much larger, so you should pick very unique words or phrases to avoid making your password list easy to guess. Passwords cannot be easily remembered either by humans or computers, so they need to be stored somewhere for others not to see them. Most people store their passwords in a plain text file on their hard drive accessible to anyone who gains access to their computer. This is why it's important to use different passwords for different sites and to change them regularly.