features in SharePoint?

Whenever we think about SharePoint, think in terms of collaboration. One of the much needed features in collaboration is on-demand functionality / feature activation. Features make it easier to activate and deactivate functionality in SharePoint.
Some points which you should note about features:

• All features needs to be copied to the “C:\Program Files\Common Files\Microsoft Shared\Web server extensions\12\Template\FEATURES\” directory. Microsoft SharePoint reads features from this directory. If you open the directory, you can find pre-installed features by SharePoint, as shown below.


• Every feature will have two XML files: ‘Feature.xml’ and ‘ElementManifest.xml’.


• SharePoint understands there is a feature by reading the feature XML file from the features folder.
• All features are identified by a unique GUID number.
• Features emit events which can be captured to write custom code. These events are captured in an assembly which needs to be registered in the GAC.
• Summarizing what we discussed, we have a ‘feature.xml’ which points to an assembly which captures the feature events for custom code. There is also another XML file which defines what exactly this feature will do.