powertools - Want to know how hex bit shank works and the history

I have tried to search this in google but I haven't found a complete explanation, so I ask this here. I also have read other answers related with hex bit socket, but it still not satisfied. How the

powertools - Want to know how hex bit shank works and the history behind it's design - Home Improvement Stack Exchange

powertools - Want to know how hex bit shank works and the history behind it's design - Home Improvement Stack Exchange

powertools - Want to know how hex bit shank works and the history behind it's design - Home Improvement Stack Exchange

powertools - Want to know how hex bit shank works and the history behind it's design - Home Improvement Stack Exchange

powertools - Want to know how hex bit shank works and the history behind it's design - Home Improvement Stack Exchange