Application Servers
A computer that runs software applications within a network
An application server is a computer or set of computers that run software applications and within a network. These applications and the results they generate are requested by clients such as web browsers. Application servers handle almost all the business logic and data-access related operations of the software that resides on them. Using an application server makes it possible for organized programming to be extended and augmented very easily. In our context, the application server is the layer between the Database and the browser. A part of it, called the web server, hosts the server side scripts and all html files. It also contains the ODBC driver and configured Data Source names that refer to relevant database. The database talks to this server through scripts and programs that also generate html and speak to the browser on the other side.
JBoss (Red Hat), WebSphere (IBM), Oracle Application Server 10g (Oracle Corporation), Sun Java System Application Server and WebLogic (BEA) are popular commercial application servers. J2EE technology from Sun has an architectural guidelines for its application servers while Microsoft's .NET has its own paradigm and architecture. Some buzzwords that are connected with application servers include Distributed Computing (a complex task is split between several computers, each of which execute one part), Software component model (a 'component farm' on a computer that functions like a store that sells electronic accessories - anyone can drop by and pick up the accessory or component they want) and Web services (a system running applications that service HTTP requests in XML format)
