Computer Vision is one cool application of machine learning techniques. CV is all about making computer programs recognize images and videos, and doing things that humans can do normally, such as tracking objects or detecting faces.
Machine learning is useful for many different computer vision tasks, as we can train a classifier to do whatever task we need to do. For example, image classification is a very important computer vision task. To solve this problem of tagging images to objects, we can use a deep learning technique (mentioned in a previous page). ImageNet is an example of a gigantic dataset (14 million images) that can be used for this task. Because of its sheer size, ImageNet is typically used in Computer Vision problems.
Other applications include facial recognition, edge detection and more! For more information, check out the CV talk.