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

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

DEWALT 1/2 in. Drive Combination Socket Set with Case (23-Piece) DWMT73813 - The Home Depot

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

Why does a driver bit shank have an indentation? - Home Improvement Stack Exchange

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DEWALT 1/2 in. Drive Combination Socket Set with Case (23-Piece) DWMT73813 - The Home Depot

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