Purpose of the key post?

What is the purpose of the key post? Doesn't the key way it's self provide constraint for the key to move in correct way? I do not understand why it has the pin which stick up into the key also.

axis, security and permutations are the main reasons

What is the purpose of the key post? Doesn't the key way it's self provide constraint for the key to move in correct way? I do not understand why it has the pin which stick up into the key also.

Without the key post it would be much easier to pick the lock with any type of bent metal object. The key post also helps support the key correctly as it turns to operate the lock.

Hope this helps.

Steve

What is the purpose of the key post? Doesn't the key way it's self provide constraint for the key to move in correct way? I do not understand why it has the pin which stick up into the key also.

Thanks, Steve C. Makes sense, to make picking more difficult.