An A-Z index or glossary of terms is well known from almost any technical book. The Layer2 Tag Directory Web Part offers a similar feature for SharePoint portals. Tags or terms are retrieved automatically from the SharePoint Term Store with a given start node. They can be linked to the corresponding SharePoint Tag Profile Pages, Hashtag Profile Pages (new in SharePoint 2013), Wiki pages, custom pages or, alternatively, via search directly to the portal content that was already classified with the selected term or tag.
The Web Part offers additional metadata navigations to browse the corporate knowledge alphabetically - cross site-collection, and independent of the content store's structure. The Web Part makes it very easy and fast to find information for users, that don't know, where the information is originally located. A great step forward and a "must-have" for employee portals, intranets, extranets and corporate Internet sites. If used as a company-wide glossary of terms it helps to build a common corporate language and understanding.
Please note, that a hierarchical tree-style navigation is additionally available with Layer2 Tag Navigation Web Part for SharePoint.
See the Features & Benefits and Installation & Setup for more detailed information.