This is a programmatically generated listing of all the topics and all of the combinations of those topics the site has to offer. All of the permutations of these topics when combined (to a level of 3) is about 750,000 individual pages!
As a programmer, you might be interested in how this list is generated more than the list itself. If so, check out the code on Github. If not, feel free to explore, but it's not likely to be fruitful. We use it for generating a comprehensive sitemap. It's kind of weird...
Checkout a list of collections or courses sorted by the date they were last updated.