Can someone tell me which it is, its the one that doesn't give off as much overspray-paint floating in the air...

I can't remember what its called, maybe its low pressure high volume....

 

I've been trying to learn a lot more about Auto Body as of late sorta on my own.

This is the direct quote from www.Autobodystore.com 's glossary.

HVLP - High volume. low pressure. Describes a paint gun that uses a high volume and low pressure of atomizing air to apply material to a surface. This provides higher transfer efficiency and lower overspray.

Hope that helps,
Mark