Drupal open source content management software

Drupal is a free software package that allows anyone to easily publish, manage and organize a wide variety of content on a website. Hundreds of thousands of people and organizations are using Drupal to power an endless variety of sites.

Drupal  is written in PHP and distributed under the GNU General Public License. It is used as a back-end system for at least 1.5% of all websites worldwide ranging from personal blogs to corporate, political, and government sites including whitehouse.gov and data.gov.uk It is also used for knowledge management and business collaboration.

 Drupal  provide a number of features, including:
Access statistics and logging
Advanced search
Blogs, books, comments, forums, and polls
Caching and feature throttling for improved performance
Descriptive URLs
Multiple-level menu system
Multiple-site support
Multiple-user content creation and editing
OpenID support
RSS Feed and Feed Aggregator
Security/new release update notification
User profiles
Various access control restrictions (user roles, IP addresses, email)
Workflow tools (Triggers and Actions)

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More information
Using Drupal
Drupal For DummiesDrupal's Building Blocks: Quickly Building Web Sites with CCK, Views, and Panels
Cracking Drupal: A Drop in the Bucket
Drupal For Dummies
Sams Teach Yourself Drupal in 24 Hours

Joomla open source content management system

Joomla! is a free and open source content management system (CMS) for publishing content on the World Wide Web and intranets. It comprises a model–view–controller (MVC) Web application framework that can also be used independently.

Joomla is used all over the world to power Web sites of all shapes and sizes. For example:
Corporate Web sites or portals
Corporate intranets and extranets
Online magazines, newspapers, and publications
E-commerce and online reservations
Government applications
Small business Web sites
Non-profit and organizational Web sites
Community-based portals
School and church Web sites
Personal or family homepages

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More useful links


Joomla! 1.6: A User's Guide: Building a Successful Joomla! Powered Website (3rd Edition)
The Official Joomla! Book (Joomla! Press)
Joomla! 1.5: A User's Guide: Building a Successful Joomla! Powered Website (2nd Edition)
Using Joomla: Building Powerful and Efficient Web Sites
Joomla! Start to Finish: How to Plan, Execute, and Maintain Your Web Site (Wrox Programmer to Programmer)
Joomla! Bible
Beginning Joomla! (Beginning from Novice to Professional)

Avanti Library Systems

Avanti Library Systems grew out of a project started in 1998 to develop a simple low cost open source library system for small libraries. A key goal was to design the system around a general model of a library system rather than design it to the needs of a specific library or type of library. This resulted in an OPAC that is simple, very efficient and adaptable to a variety of libraries and situations.

The design philosophy of Avanti Library Systems emphasizes simplicity, usability and careful design. This results in software that is:
Easy to use. User interfaces are carefully designed, consistent and simple, offering the user only what they need when they need it. This reduces costs by minimizing the need for extensive training of library staff and patrons.
Small, efficient and self-contained. With careful minimalist design the software can run effectively on very modest hardware. By keeping systems as self-contained as possible, external dependencies are reduced or eliminated altogether. MicroLCS requires no third party software other than Java to run.
Flexible and powerful. By building upon a simple well thought out architecture, power and flexibility are not sacraficed for simplicity. MicroLCS is a fully functional client/server library system. Although simple, it has a flexibility and ease of use that are rarely found in any other OPAC in its class

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Useful links 
Using Open Source Systems for Digital Libraries
Open Source Integrated Library Systems (Library Technology Reports)
Open Source Systems in Libraries
Open source library management systems: a multidimensional evaluation.: An article from: Australian Academic & Research Libraries

Emilda library system

Emilda is a complete Integrated Library System that features amongst others an OPAC, circulation and administration functions, Z39.50 capabilities and 100% MARC compatibility. MARC compatibility is achieved using Zebra in conjunction with MySQL.

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Source code