I am new to calculus and currently learning differentiation. I understood that the first derivative indicates the slope of the function and the second derivative indicates the rate at which the slope is increasing or decreasing. I have seen some questions asking to find the 3rd derivative of functions and can't understand what would be its geometrical/physical significance. I would appreciate if someone could explain why 3rd derivatives are important. Thanks in advance :)
(Originally  by AJAY.)  What is the geometric, physical, or other meaning of the third derivative of a function at a point?  If you have interesting things to say about the meaning of the first and second derivatives, please do so.
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