What is adversarial machine learning?

This article is part of Demystifying AI, a series of posts that (try to) disambiguate the jargon and myths surrounding AI. To human observers, the following two images are identical. But researchers at Google showed in 2015 that a popular object detection algorithm classified the left image as "panda" and the right one as "gibbon." And oddly enough, it had more confidence in the gibbon image. The algorithm in question was GoogLeNet, a convolutional neural network architecture that won the 2014 ImageNet Large Scale Visual Recognition Challenge (ILSVRC 2014). The right image is an "adversarial example."