artificial intelligencemachine learningand deep learning what do the representations learned by deep-learning algorithm look likelet' examine how network several layers deep (see figure transforms an image of digit in order to recognize what digit it is layer layer layer layer original input final output figure deep neural net work for digit classificat ion as you can see in figure the network transforms the digit image into representations that are increasingly different from the original image and increasingly informative about the final result you can think of deep network as multistage information-distillation operationwhere information goes through successive filters and comes out increasingly purified (that isuseful with regard to some tasklayer representations layer representations layer representations layer representations (final output original input layer figure layer layer layer deep represent at ions learned by digit -classificat ion model so that' what deep learning istechnicallya multistage way to learn data representations it' simple idea--butas it turns outvery simple mechanismssufficiently scaledcan end up looking like magic understanding how deep learning worksin three figures at this pointyou know that machine learning is about mapping inputs (such as imagesto targets (such as the label "cat")which is done by observing many examples of input and targets you also know that deep neural networks do this input-to-target licensed to