Web architecture

When you are visiting web sites, you do so using your web browser. Talking about web architecture, we often talk about the client and the server, and subsequently the client-server architecture. In that an architecture your browser is the client, and the server that provides the files you see is the server.

Note that your browser is not your only connection to the Internet, as there are other ways of sharing files than using the HTTP protocol.

Server

The server is software running on a computer, responding to requests from the client. The web page and database exists on the server's local file system. The server retrieves and transmits file to the client.

Client

Once connected, the user can access the web trough software, called browsers (e.g. Firefox, Chrome, Safari). These browsers can locate and display information from the web.

Communication between the client and the server is done by an agreed transmission language, or protocol, e.g. HyperText Transfer Protocol (HTTP).

The user requests a web page through the browser, which communicates this to the server. The browser then waits for the web page to be delivered, which typically is a file containing HTML. When the file is recieved, the browsers renders the page based on the files received.

Cloud

The cloud is a network of servers for the purpose of sharing resources.

Network

Computers, both servers and clients, that are connected together is a network. Each server or client is a node in the network, and their connections can be illustrated using edges between the nodes.

Computers that are close together (within a single department or building) make up a local area network (LAN). A network of computers that covers a wide area, such as several buildings, cities, or even larger areas, is called wide area network (WAN). The largest WAN in existence is the Internet.