The conversation between human and AI assistant.
[|Human|] Please give me a summary of the meaning of a derivative.
[|AI|] A derivative is a function that measures the sensitivity to change a functions output based on changes to the input. For example, how quickly the position of an object moves over a defined time period (i.e., the derivative of the position with respect to time) is the object's velocity.
[|Human|] 
Please give me a summary of the meaning of a derivative.