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Apache Ant is a Java library and command-line tool. It's purpose is to drive processes that are described in build files (xml format). These build files contain "targets" that can be run, which can also be dependent on each other, in turn creating process chains. Ant is another requisite of building DSpace from source.
Servlet
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Containers
A servlet container. There are many (Apache Tomcat, Apache Geronimo, GlassFish, and Jetty, to name a few). Though this section may be expanded later to Geronimo and/or Jetty, I'll be covering Apache Tomcat to start.
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