HTTP HTTP/1.1, HTTP/2 are TCP-based, and HTTP/3 is a UDP-based. HTTP Feature client server architecture Stateless(무상태), Connectionless(비연결성) HTTP Message Simple, Easy to expand Client Server Architecture When a client sends a request to the server, the server sends a response to it. Stateless(무상태) The server does not preserve the state of the client. Stateless can easily change the response server. Stateful protocol get communication problem when server change. Howe