Web Server Part 1: Apache/Nginx Basics

Abstract

The web server is the software that makes the website(s) accessible. The web server does this by listening on the ports 80 and 443 and serving the files in certain directories as responses to requests received on those ports. Port 80 is the default port for HTTP (Hypertext Transfer Protocol), and port 443 is the port for the encrypted HTTPS variant (the S meaning Secure). Even though web servers can usually be configured to listen on other ports, a client like a web browser or a web crawler will always send HTTP and HTTPS requests without an explicit port indication to ports 80 and 443, respectively; if the user does not specify a protocol, clients will usually fall back to HTTP.