Server:

 The software that distributes the information and the machine where the information and software reside is called the server.

 • provides requested service to client

• e.g., Web server sends requested Web page

Client:

The software that resides on the remote machine, communicates with the server, fetches the information, processes it, and then displays it on the remote machine is called the client. 

• initiates contact with server (“speaks first”)

• typically requests service from server

• Web: client implemented in browser

Web server:

 Software that delivers Web pages and other documents to browsers using the HTTP protocol

 Web Page:

 A web page is a document or resource of information that is suitable for the World Wide Web and can be accessed through a web browser.

 Website:

 A collection of pages on the World Wide Web that are accessible from the same URL and typically residing on the same server.

 URL:

 Uniform Resource Locator, the unique address which identifies a resource on the Internet for routing purposes.

Client-server paradigm:

 The Client-Server paradigm is the most prevalent model for distributed computing protocols. It is the basis of all distributed computing paradigms at a higher level of abstraction. It is service-oriented, and employs a request-response protocol.

 A server process, running on a server host, provides access to a service. A client process, running on a client host, accesses the service via the server process.The interaction of the process proceeds according to a protocol.

 The primary idea of a client/server system is that you have a central repository of information—some kind of data, often in a database—that you want to distribute on demand to some set of people or machines.