Categories and tags are a great resources for helping you group common topics related between your blog posts. For instance if you were writing for the Buchhof Bulletin, you might want all of the posts that are related to the Senior School Students, to show up in one common place. By creating a Category like SrS, you could then check a box for each post related to the Senior School prior to publishing it and it would make sure that post got grouped with all the other SrS posts on the website. Categories can also be added to your menu as a way of helping people navigate to some of the big topics for your website.