In BJJ circles, the 50Fifty Guard has been in vogue for the past several years. The first time I saw the position was in the late 90's at a Shooto seminar where it was introduced as a leg locking position.
The Armbar from Guard was probably one of the very first techniques you've ever learned when you first started BJJ.
I'm going to show you the classic 5 point Armbar from Guard but with a truck tonne of details.
The Kimura is a shoulder lock. There are two shoulder locks: Either with the hand going up (generally called the "Americana") or the hand going down. I'm going to talk about the hand going down. This is typically referred to at the Kimura.