Apache Tomcat is the servlet container that is used in the official Reference Implementation for the Java Servlet and JavaServer Pages technologies. The Java Servlet and JavaServer Pages specifications are developed by Sun under the Java Community Process.

Apache Tomcat is developed in an open and participatory environment and released under the Apache Software License. Apache Tomcat is intended to be a collaboration of the best-of-breed developers from around the world.

Different versions of Apache Tomcat are available for different versions of the Servlet and JSP specifications. The mapping between the specifications and the respective Apache Tomcat verisons is:
Servlet/JSP Spec     Apache Tomcat version
2.5/2.1     6.0.x
2.4/2.0     5.5.x
2.3/1.2     4.1.x
2.2/1.1     3.3.x

The releases are described in more detail below to help you determine which one is right for you. More details about each release can be found in the associated release notes.

Please note that alhough we offer downloads and documentation of older releases, such as Apache Tomcat 3.x and 4.x, we strongly encourage users to use the latest stable version of Apache Tomcat whenever possible. We recognize that upgrading across major version may not be a trivial task, and some support is still offered on the mailing list for users of old versions. However, because of the community-driven support approach, the older your version the less people would be interested or able to support you.