Application Server

An application server is a software framework that provides an environment where applications can run, no matter what the applications are or what they do. It is dedicated to the efficient execution of procedures (programs, routines, scripts) for supporting the construction of applications.
The term was originally used when discussing early client–server systems to differentiate servers that run SQL services and middleware servers from file servers.

Later, the term took on the meaning of Web applications, but has since evolved further into more of a comprehensive service layer. An application server acts as a set of components accessible to the software developer through an API defined by the platform itself. For Web applications, these components are usually performed in the same machine where the Web server is running, and their main job is to support the construction of dynamic pages. However, present-day application servers target much more than just Web pages generation, they implement services like clustering, fail-over and load-balancing, so developers can be focused just on implementing the business logic.
Normally the term refers to Java application servers. When this is the case, the application server behaves like an extended virtual machine for the running applications, handling transparently connections to the database at one side, and connections to the Web client at the other.
Other uses of the term may refer to the services that a server makes available or the computer hardware on which the services run.

PowerPoint Presentation

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ApplicationServer.ppt

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