Looking at the photos and videos on this site, there seems to be a big variation in how people hold their bows. Some hold them at the end, like a violin bow (as I do) and others hold them in the centre of the bow, especially if it's a very arched bow. Some people also hold it daintily between thumb and fingers and others grasp it in their fist like a caveman with a primitive stone tool!
Since there appears to be no right or wrong way of doing it, I wondered what the advantages and disadvantages of the various grips are. The shape of my bow (quite flat) restricts me to holding it at the end, but I think if I had a more arched bow I would not be comfortable holding it in the middle - I'd feel like it would wobble about from side to side!