What is the best way to ensure secure passwords?

Creating a mix of letters, numbers, and symbols is the best way to ensure secure passwords because it significantly increases the complexity and unpredictability of the password. This complexity makes it much more difficult for unauthorized individuals or automated tools like password-cracking software to guess or crack the password. When a password includes a variety of character types, it expands the possible combinations exponentially, leading to stronger overall security.

Utilizing only letters and changing passwords monthly does not guarantee security because simple variations can still be predictable and vulnerable to attacks. A simple word shared with friends poses substantial security risks, as sharing any form of password can lead to unauthorized access. Additionally, sticking to the same password for all accounts compromises security since if one account is breached, all accounts with that password become vulnerable. Thus, a mix of different character types is essential for maintaining robust password security.