Web servers can be hardware or software, running alone or jointly. 

Web servers are computers with additional processing power and memory that hold the application's back-end code and static assets like photos and JavaScript, CSS, and HTML files. 

Web servers take HTTP requests from clients like web browsers, process them, and return responses. The answer might be static (image/text) or dynamic (shopping cart total).

 

Popular web servers include Apache, Nginx, and IIS.