ffuf (Fuzz Faster U Fool) is a fast web fuzzer written in Go. It is designed for discovering hidden resources and testing web applications by fuzzing URLs, HTTP headers, parameters, and POST data. ffuf supports directory and file discovery, virtual host discovery, parameter fuzzing, recursive scanning, multiple wordlists, response matching and filtering, configurable request rates, and several output formats. It can be used for web application security testing, penetration testing, and content discovery on authorized targets.