Kava is a root, (you can get it whole, powdered or in capsules) it is relaxing and is similar to benzos in that it can have relaxing/calming/anticonvulsant effects, but it feels sort of different to me. There is some suggestion that it may work in the brain on GABA in a similar manner to benzos, but studies on this have been conflicting and it may also have other mechanisms of action. It's not fully understood how it works. Feel free to post in the megathread if you have any questions that aren't answered there.