To put it simply, it's a crochet hook with a hole at the end of the handle. You run a long chord through that hole and then knit using the hook end. There are "how-to" videos at www.leisurearts.com if you're interested in seeing how it works. (I didn't check out the videos until this morning - probably would have taken care of some mild frustration if I had watched them first!) Overall, pretty simple and fun to do......otherwise I wouldn't do it!
I can't say if I like "knitting" this way better than the traditional way quite yet. It's just fun to play with something new every now and then. :)
Take care, thanks for stopping, and please feel free to come again! - Elizabeth