Definition - What does Web Server mean?
A Web server is a system that delivers content or services to end users over the Internet. A Web server consists of a physical server, server operating system (OS) and software used to facilitate HTTP communication.
A Web server is also known as an Internet server.
Techopedia explains Web Server
The most simple definition is that a Web server runs a website by returning HTML files over an HTTP connection. This definition may have been true in the early days of the Internet, but the line has blurred between websites, Web applications and Web services, etc. For example, a server that delivers an XML document to another device can be a Web server. A better definition might be that a Web server is any Internet server that responds to HTTP requests to deliver content and services.
Depending on context, the term can refer to the hardware or Web server software on the server. For example, saying that you have "10 Web servers at the Web farm" is just as accurate as, "The IIS Web server is on the machine that has 32 GB of RAM."
In terms of software, there have been literally hundreds of Web servers over the years, but Apache and Microsoft's IIS have emerged as two of the most popular systems.