Is the inverse of a function always a function? Why or why not? In simple terms

No, the inverse of a function is not always a function. This is because for a function to have an inverse, it must satisfy the property that each input in the domain corresponds to exactly one output in the range. If there are multiple inputs that map to the same output, then the inverse of the function would not be able to uniquely map each output back to its original input, and therefore would not be a function.