(By analogy with "applet") A Java program that runs as part of a network service, typically an HTTP server and responds to requests from clients.

The most common use for a servlet is to extend a web server by generating web content dynamically. For example, a client may need information from a database; a servlet can be written that receives the request, gets and processes the data as needed by the client and then returns the result to the client.

Applets are also written in Java but run inside the JVM of a HTML browser on the client. Servlets and applets allow the server and client to be extended in a modular way by dynamically loading code which communicates with the main program via a standard programming interface.

Servlets are more flexible than CGI scripts and, being written in Java, more portable.

The spelling "servelet" is occasionally seen but JavaSoft spell it "servlet". There is no such thing as a "serverlet".

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