Plone 3.1.5.1

Plone is a ready-to-run content management system that is built on the powerful and free Zope application server. Plone is easy to set up, extremely flexible, and provides you with a system for managing web content that is ideal for project groups, communities, web sites, extranets and intranets.
Plone is easy to install. You can install Plone with a a click and run installer, and have a content management system running on your computer in just a few minutes.
Plone is easy to use. The Plone Team includes usability experts who have made Plone easy and attractive for content managers to add, update, and mantain content.
Plone is international. The Plone interface has more than 35 translations, and tools exist for managing multilingual content.
Plone is standard. Plone carefully follows standards for usability and accessibility. Plone pages are compliant with US Section 508, and the W3Cs AAA rating for accessibility.
Technical overviewPlone is a content management framework that works hand-in-hand and sits on top of Zope, a widely-used Open Source web application server and development system. To use Plone, you dont need to learn anything about Zope; to develop new Plone content types, a small amount of Zope knowledge is helpful, and it is covered in the documentation.
Zope itself is written in Python, an easy-to-learn, widely-used and supported Open Source programming language. Python can be used to add new features to Plone, and used to understand or make changes to the way that Zope and Plone work.