The power of XOOPS lies in the modular implementation of its features - it is written in an object-oriented manner. This allows for better scalability, extensibility and customization.
XOOPS consists of:
the 'core' XOOPS program, which provides the basic operating and administrative framework
a series of official modules that serve the basic needs of a dynamic site
as many optional modules as you might want to provide additional functionality.
New functions can be added through a simple module installation process. This modular approach makes XOOPS highly customizable. You only need to install those modules you find useful and you can remove them at any time - there is no need to burden your site with unnecessary code and your site can be configured to have just what you need.