Final answer:
A password that is at least seven characters long and uses three of the following categories (uppercase, lowercase, numbers, and special characters) is called a complex password.
Step-by-step explanation:
A password that is at least seven characters long and uses three of the following categories (uppercase, lowercase, numbers, and special characters) is called a complex password. A complex password is designed to be more secure and harder to guess or crack.
For example, a complex password could be something like 'Pasw0rd123'. It is at least seven characters long, includes uppercase letters, lowercase letters, numbers, and a special character.
Using a complex password helps protect personal information and online accounts from unauthorized access and potential hacking attempts.