How do I use this?
On the left of the screen, there is a light-blue region. In this region are shown the top-level categories from the browse-tree you picked.
If you want to see all the resources associated with one of these categories, click on it, and a list of the resources will appear here, as clickable links.
If instead you would like to open up the top-level category to explore the subcategories, then click on the PLUS (+) symbol for that top-level category,
and the tree will expand to show a list of the 'child' subcategories of that category. If you want to contract the tree again, click the MINUS (-) symbol
next to the category you wish to contract. This can be repeated
wherever you see a + or - symbol.
If you want to see all the resources associated with a particular category or sub-category, simply click on its name, and a list of the resources will appear here, as clickable links.