Before the boom of open source software, a high-end, fully-functional, feature-rich content management system could cost you upwards of $50,000. Low and behold, from the good graces of the original creators of Mambo, came the content management system hundreds of thousands of publishers have come to love named Joomla!
Joomla 1.5! is not so much of a branch off the original Joomla! 1.0 as it was an entirely new project altogether. Many of the features that version 1.0 lacked (W3C standards, search engine friendly URLs, better framework) were incorporated into Joomla 1.5!
Debatedly one of the most robust content management systems out there, Joomla 1.5! is used for building websites ranging from social networking to corporate, real-estate to e-commerce, and news to blogs. Want to use Joomla! for something else in mind? Chances are there’s an extension for that.
Its templating/theme system uses simple blocks of code you plug into a single index.php file instead of using multiple files that piece together your design. This makes it drastically simple to create your own custom themes.
Joomla!’s only major drawback is its content organization. You have content items (a document) that are stored in categories (a folder) that are stored in sections (a filing cabinet). Say you have this organizational pattern: Instruments > Woodwinds > Clarinets > Mouthpieces. You could not use a multiple level tree-structure to do this. You would have to have section named Instruments and use a category named Mouthpieces. (Instruments > Mouthpieces).
Built-in search engine friendly URLs, XHTML & CSS valid, user registration, more extensions than you can shake a stick at (3500+), and the peace of mind knowing that you have a highly active community of 205,000 strong behind you, make this web application worth spending time with.