Oh! Yep - it is one of those 'machines' that allows you to use your body weight to exercise with!
In other words it could be just another 'name' for training! It could be as old fashoined as the ankle boots you tie yourself to a bar to - to do upside down sit ups - or it could be the "zenergistic" exercises (I kid you not) that balance body and mind, but is probably one of those 'Pilates' style machines
And they're not bad stuff! They do allow you to use your body weight sensibly and safely - and are usually more fun and less threatening to use than standard weights machines!
I did a short research project on them about 4 years ago for a local (very small) gym prior to purchase. And they came out very favourably.
Unfortunately someone else did the follow up project, so I don't know about customer satisfaction!
Try it out and let us know....