httpd is a web server software that serves web pages to users over the internet. It processes requests from clients, typically web browsers, and delivers the requested content, such as HTML files, images, and scripts. httpd is commonly used to host websites and can handle multiple requests simultaneously. The most popular version of httpd is the Apache HTTP Server, which is open-source and widely supported. It is known for its flexibility, allowing users to customize configurations and add modules for enhanced functionality. httpd plays a crucial role in the functioning of the World Wide Web.