1. Routerhttps://expressjs.com/en/api.html#router Express - Node.js web application framework expressjs.com - Router는 Controller와 URL을 관리 - You can think of it as a “mini-application”  - 작업중인 주제를 기반으로 URL을 그룹화# URL# Global/ -> Home/join - Join/login -> Login/search -> Search# User/user/edit -> Edit User/user/delete -> Delete User# Videos/videos/watch - > Watch vidoo/videos/edit -> Edit video/vid..