If you wish to explore a new concept, perhaps ask duckduckgo "what is ctf" an you may well get a response such as:

    CTF stands for Capture The Flag, which is a cybersecurity competition where participants find hidden "flags" in vulnerable programs or systems to test and develop their security skills. There are two main types of CTFs: jeopardy-style, where teams solve various challenges for points, and attack-defense, where teams defend their systems while trying to exploit their opponents'.