A web server is a computer system that stores, processes, and delivers web pages to users over the internet. When you enter a website's address in your browser, the web server receives the request and sends back the appropriate content, such as HTML files, images, and videos. This process allows users to view and interact with websites seamlessly. Web servers use the HTTP (Hypertext Transfer Protocol) to communicate with web browsers. Popular web server software includes Apache, Nginx, and Microsoft IIS. These servers can host multiple websites and handle many requests simultaneously, making them essential for the functioning of the internet.