Final answer:
CAPTCHAs, login throttling, and account lockouts after multiple failed attempts are security measures used to prevent brute-force password guessing attacks.
Step-by-step explanation:
CAPTCHAs, login throttling, and locking out accounts after a set number of failed logins are all useful techniques to stop or delay brute-force password guessing attacks. These security measures are critical to protect users' accounts from unauthorized access. CAPTCHAs challenge users to complete tasks that are easy for humans but difficult for automated scripts, thus preventing bots from mass-guessing passwords. Login throttling slows down the process by introducing delays after failed login attempts, which makes automated attacks less efficient. Locking out accounts after numerous consecutive failed login attempts prevents further guesses and alerts the legitimate user and system administrators of a possible attack. These measures add layers of security to safeguard against the potential compromise of user accounts.