Which of the following characteristics defines a secure password?

A secure password is best defined as one that is long, complex, and includes a mix of letters, numbers, and symbols. This combination enhances its strength and makes it much more difficult for unauthorized users to guess or crack the password. A longer password generally provides a greater number of potential combinations, making it exponentially harder for attackers to brute-force into an account. Including a variety of character types—such as uppercase and lowercase letters, numbers, and special characters—further increases the complexity and unpredictability of the password. This multifaceted approach to password creation is recommended by security experts and organizations as an essential practice to safeguard sensitive information.

In contrast, options that suggest passwords should be easy to remember and consist only of letters, be short and include birthdays, or consist solely of special characters represent less secure practices. Easy-to-remember passwords often lead to simpler, more predictable combinations that can be easily exploited. Short passwords limit the number of possible variations, making them vulnerable to attacks. Using identifiable information, like birthdays, is also risky because such data can often be found or guessed. Meanwhile, passwords made up only of special characters may not be practical for users and can also create compatibility issues across different systems and applications.