Tha would be so the sticks dont dry …

After search somemore I found the following and pretty much answered my own question. For those also wondering, here is a response by Marc S.

“… Oil sticks and oil bars are just two different terms for the same thing. The medium isn’t quite well established to have a standardized name, so every manufacturer calls their version something different. “Oil stick” is Sennelier, “Oil bar” is Winsor & Newton. Either way (and ditto for Shiva PaintStick), it is basically oil paint with enough wax to hold make it hold its shape. It will still mix like oil paint (although I don’t think people generally do this on a palette), and will still dry / cure like oil paint. In fact, just like a blob of oil paint you squeeze onto your palette and leave too long, it starts to dry from the outside in, and you have to peel away the “skin” that forms to get to the usable stuff inside.

Oil pastel is different. Same basic ingredients – pigment, oil, and wax – but the binder is *mostly* wax, with just a little oil to improve its handling properties. As a result, color don’t really mix like they do with oil paint. It is much more like pastel, or crayon (which is oil pastel without the oil) – the belnding is more optical than physical. And it won’t ever completely dry or cure like an oil painting, although it might dry a little. The sticks themselves are the same texture all the way through, and do not form skins.”