What Is a Web Server
Essentially, a Web Server is a software application that listens for client connectgions on a specific network port.
When a connection is made, the Web Server then waits for a request from the client application. The client is usually a Web browser, but it could also be a Web site indexing utility, or perhaps an interactive telnet session.
The resource request, usually a request to send the contents of a file stored on the server, is always phrased in some version of the H.T.P (HTTP).