Tomcat - Projet Apache Jakarta

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

• Tomcat 5.0.x - 5.5.x
• Servlet : 2.4
• JSP Spec : 2.0
• Tomcat 4.1.x
• Servlet : 2.3
• JSP Spec : 1.2
• Tomcat 3.3.x
• Servlet : 2.2
• JSP Spec : 1.1

Tomcat 5.5.x. Tomcat 5.5 is the current focus of development.
While it supports the same Servlet and JSP Specification versions as Tomcat 5.0.x, there are significant changes in many areas under the hood, resulting in improved performance, stability, and total cost of ownership.

Tomcat 5.0.x. Tomcat 5.0 improves on Tomcat 4.1 in many ways, including:

• Performance optimizations and reduced garbage collection
• Refactored application deployer, with an optional standalone deployer allowing validation and compilation of a web application before putting it in production
• Complete server monitoring using JMX and the manager web application
• Scalability and reliability enhancements
• Improved Taglibs handling, including advanced pooling and tag plugins
• Improved platform integration, with native Windows and Unix wrappers
• Embedding of Tomcat using JMX
• Expanded documentation

http://jakarta.apache.org/tomcat/