Web systems are hypertext document systems that are relatively new to the computing world.
The fundamental elements of a Web system are the client browser, the network, and a Web server.
A Web application is a Web system that delivers business logic.
HTTP is the primary protocol for communication between clients and servers.
HTTP is a connectionless protocol. Each time a client requests a document from a Web server, a new connection must be established with the server.
As identifiers of network resources, URLs or URIs can reference Web pages, images, applets, and other resources on the network.
Web pages are documents that are requested by the client and delivered by the Web server.
The principal formatting language for Web pages is HTML. It tells the browser how to render the content on the screen.
Forms allow users to enter input through a Web page.
Frames allow multiple Web pages to be active for a user at the same time.
Session management is the tracking of a particular user's progress through the application, even across Web pages. Cookies can be used to help manage client state on the server.
Enabling technologies are development environments that provide the infrastructure for building Web applications.Some popular technologies are CGI, Active Server Pages, JavaServer Pages, servlets, and Web server APIs.