Modern humans share a gesture of acknowledgement with each other that goes beyond verbal communication, or a simple handshake. That gesture is the head nod, and it can be given in passing, as a way of ...

Youre walking down the street and make eye contact with a dude going the opposite way-what do you do? As a recent revealed, if youre like a lot of guys, you probably do some kind of nod-a subtle, some ...