Cloudflare Turnstile is a CAPTCHA-alternative solution designed to verify human users and prevent bot traffic from accessing websites. It works by running a series of non-intrusive JavaScript challenges and behavioral analysis in the background, without typically requiring users to solve puzzles or decipher distorted text. This process helps to distinguish legitimate human visitors from automated bots, protecting forms, logins, and other critical website areas from spam, abuse, and credential stuffing attacks. The script dynamically loads and executes these challenges based on real-time threat intelligence, aiming to block malicious automated traffic while providing a seamless experience for genuine users.