When you click on the Add "someones" Widget to your website.
HubPages provides you with an HTML program which you can Copy and Paste to your blog or website. When you open the website or blog in a browser the code provides a thumbnail of the person's profile picture and a list of their most recent hubs.
I use it to provide some of my own blogs with updates from my hubs in place of an RSS feed to my hubpages account.
Simply it is a more attractive version of an RSS feed.