Alfresco is a Free/Libre enterprise content management system for Microsoft Windows and Unix-like operating systems. Alfresco comes in three flavors. Alfresco Community Edition is free software, LGPL licensed open source and open standards. Alfresco Enterprise Edition is commercially & proprietary licensed open source, open standards and enterprise scale. Its design is geared towards users who require a high degree of modularity and scalable performance. Alfresco Cloud Edition (Alfresco in the cloud) is the SaaS version of Alfresco that extends Alfresco’s document management capabilities across the firewall to support you when you want to easily and securely collaborate with colleagues or other organizations.
Alfresco includes a content repository, an out-of-the-box web portal framework for managing and using standard portal content, a CIFS interface that provides file system compatibility on Microsoft Windows and Unix-like operating systems, a web content management system capable of virtualizing webapps and static sites via Apache Tomcat, Lucene indexing, and Activiti workflow. The Alfresco system is developed using Java technology.
Description by wikipedia
“Learn Alfresco in an hour…”
sure it needs more than that 🙂