Let's face it. Most of us have been beaten over the head with lectures on password complexity. It isn't a sexy subject but we are talking about the keys to your castle. A lot of technology and techniques developed to guess or extract your passwords. If someone knows your username, which is relatively easy to obtain, the password part needs to be strong. In technical terms it needs a high level of entropy. I have noticed the trend is to create passwords and replace certain letters with numbers. (Pa55word). This is a pattern that is well known by hackers and the tools they use are designed to anticipate it.
The password alone is not the problem. Re-using passwords for multiple accounts like you bank, email, computer and so on are a huge problem. If one of your passwords are cracked, hackers will try to use these credentials on your other accounts. The best way to avoid crackable passwords is to use a password generator. They are usually combined with a password safe. (link). These tools will generate a highly complex, unique password and save it in and encrypted file.
