Factoid
History of the handshake.
Shaking hands was a way of making sure that people were not carrying a weapon such as a knife or swoard. When you shook hands, you were saying:" Look, I don't have a weapon. I trust you, let's be friend!"
Factoid: / ˈfæktɔɪd /: a small and quite interesting piece of information that is not important
Weapon: /wepən/ : something that you use to fight with or attack someone with, such as a knife, bomb, or gun: They all had sticks which they planned to use as weapons.