From a user's perspective, the Web is a collection of documents or pages which contain text, images, and hypertext links to other pages. By pointing, clicking, and traversing the links, the user has instant access to a distributed collection of information. The Oracle Web Listener merges the techniques of information retrieval and hypertext to create a powerful global information system.
The Oracle Web Listener works on a simple client-server model. Clients send requests to the Oracle Web Listener. The listener interprets a request by reading the URL, finds (or generates) the information requested, and returns that information to the client in the form requested.
You can run several Oracle Web Listeners on the same machine by giving each a dedicated port. Having multiple Web Listeners is a good way to balance the load among various applications.
The language that the Oracle Web Listener uses to communicate with its clients is HyperText Transfer Protocol (HTTP). The Web Listener implements version 1.0 of the HTTP protocol as described in the IETF HTTP Working Group (http://www.ics.uci.edu/pub/ietf/http/). All Web clients must be able to speak the HTTP protocol in order to send and receive hypermedia documents.
HTTP is an application level protocol with the lightness and speed necessary for distributed, collaborative, hypermedia information systems. It is a generic, stateless, object-oriented protocol which can be used for many systems, through extension of its request methods (commands).