TAXONOMY

http://metroecho.net/allsites/taxonomy/

Taxonomy is the practice and science of classification. The word finds its roots in the Greek τάξις, taxis (meaning 'order' or 'arrangement') and νόμος, nomos (meaning 'law' or 'science'). Taxonomy uses taxonomic units, known as taxa (singular taxon). ( wikipedia)

This function or module groups content and it serves the same purpose as "Folders" in windows.

It has the following added features...

1. Menus with types of content can be displaied on selected pages.

2. You can require content to be taged when created by users and then will sort automaticaly.

3. One document or content can be in several catagories, yet is saved only in one location.  

From Admin Help...

The taxonomy module allows you to categorize content using various systems of classification. Free-tagging vocabularies are created by users on the fly when they submit posts (as commonly found in blogs and social bookmarking applications). Controlled vocabularies allow for administrator-defined short lists of terms as well as complex hierarchies with multiple relationships between different terms. These methods can be applied to different content types and combined together to create a powerful and flexible method of classifying and presenting your content.

For example, when creating a recipe site, you might want to classify posts by both the type of meal and preparation time. A vocabulary for each allows you to categorize using each criteria independently instead of creating a tag for every possible combination.

Type of Meal: Appetizer, Main Course, Salad, Dessert

Preparation Time: 0-30mins, 30-60mins, 1-2 hrs, 2hrs+

Each taxonomy term (often called a 'category' or 'tag' in other systems) automatically provides lists of posts and a corresponding RSS feed. These taxonomy/term URLs can be manipulated to generate AND and OR lists of posts classified with terms. In our recipe site example, it then becomes easy to create pages displaying 'Main courses', '30 minute recipes', or '30 minute main courses and appetizers' by using terms on their own or in combination with others. There are a significant number of contributed modules which you to alter and extend the behavior of the core module for both display and organization of terms.

Terms can also be organized in parent/child relationships from the admin interface. An example would be a vocabulary grouping countries under their parent geo-political regions. The taxonomy module also enables advanced implementations of hierarchy, for example placing Turkey in both the 'Middle East' and 'Europe'.

The taxonomy module supports the use of both synonyms and related terms, but does not directly use this functionality. However, optional contributed or custom modules may make full use of these advanced features.

 

http://drupal.org/node/774892