Back then,Knife throwing was used as an act,it was for peoples satisfaction,they would even have live shows on the way of throwing  a knife,and the target would be a human,as you could see in the photos,the thrower has to avoid the persons body ,but has to drive the knife as closes to the persons body.

But now a days,I think knife throwing is just used for our own entertainment,it can also revolve around the category of sports,on the history page,I mentioned the anneal knife throwing competition that professionals knife throwers enter ps.the thrower is giver a certain distance depending of their height,