Tough to tell from the pic, but maybe a cordyline of some sort. I wouldn't keep it in full sun. I'd give it morning sun only for now, repot it in some good soil and keep it well watered, maybe a little Superthrive if you have it.

Looks like a dying Dracaena fragrans to me...

Definitely looks like a Dracaena reflexa that was shade grown. It does well both indoors and outdoors, if you keep it outdoors make sure to put it in shade, it looks like it may have had some sun damage.
Good luck!
-Alex

Yes, it is a Dracaena. But in that emaciated state it's a bit difficult to say which one. They grow well from cuttings but a cutting from that one might be a bit too weak to do anything. The best advice would be to give it shade/bright light, water but don't let it get soggy. And the final ingrediant is time. They usually do recover quite well.