Centuries ago, monks who took a vow of silence developed their own hand signs, with hundreds of gestures, that are still in use today. Plus, how do speakers of different languages distinguish similar shades and tints of colors such as red, yellow...
Centuries ago, monks who took a vow of silence still had to communicate about everyday activities in the monastery, from gardening to equipment repair. So they developed their own hand signs, with hundreds of gestures for various words and ideas...