UO Second Age

Under the target menu in the Razor Hot key tab the following are listed:
target Enemy
target Criminal
target Grey

Does anyone have any idea how these are defined?

IE is Enemy considered red? or chaos/order or something that has targeted/attacked you? Criminal I'm guess is a gray player, or is it a red?
and Gray I'm guess is gray (neutral npc) and not a gray player.. anyone have any idea/input on the actual function of these commands ?

Enemy is an "orange" or enemy guild member.
Criminal is, obviously a criminal.
Gray is just something that can be attacked, but not a criminal. Like a bird, or a cow.

enemy can also be classified as opposing team members in events.