A file (Metadata file) summarising the set of spatial datalayers which can be accessed under "Mapping Application" can be downloaded here.
This file gives information on the Category, Title, Description, Source, Contact Person and Contact e-mail address for each datalayer. The descriptions are not comprehensive and the use is referred to the relevant contact person for further information.
Metadata is "data about data". It provides information about an item's content. For example, it describes when the data was created, by whom, the methods used, how the data was formatted, a short description of the contents, and possible restrictions in its use. In the context of Geographic Information Systems (GIS), the reader is referred to the ESRI webpage on metadata.