What is JVS? The history behind the standard?

What is the difference between JAMMA and Jamma Video Standard (JVS)? Why was the change needed?

I'm just interested in the historical reasoning for the evolution. JAMMA was a huge benchmark in the coin-op lifeline.

http://jvspac.kirurg.org/

Theres a short introduction to JVS here.

For a start, its just more capable than plain jamma and its easier to support a variety of devices such as lightguns, steering wheels and suchlike. JAMMA only supports 3 buttons and mono sound as standard as you probably know. JVS is basically better and addresses all of JAMMA's fallbacks. its a lot more complicated though and I think its an actual digital software protocol.

JVS allowes to have a common connection for wheels, trackballs, guns, etc. Unlike Jamma that needed propietary company harnesses in order to do things a Jamma harness couldn't support. JVS is great but it coud have been design better although I think it was design that way to keep costs down. I'd never get into JVS, is pointless given that current gen consoles are pretty much up to par with JVS since the DC.