It's all about the input. You can't always give all a function's inputs at the same time. Professor Graham Hutton explains about curried functions.

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This video was filmed by Graham Hutton and edited by Sean Riley.

Computer Science at the University of Nottingham: https://bit.ly/nottscomputer

Computerphile is a sister project to Brady Haran's Numberphile. More at http://www.bradyharan.com