Machine learning enables us to build systems that can predict the world around us: like what movies we'd like to watch, how much traffic we'll experience on our morning commute, or what words we'll type next in our emails. There are many types of models and tasks. Face detection models transform raw image pixels into high level signals (like the presence and position of eyes, noses, and ears) and then use those signals to locate all faces in an image. Time series models can use sensor measurements to extract long-term trends and seasonal patterns in order to predict future observations. Text prediction models extract information about the meaning of past sentences, grammaticality, and emotions in the text in order to predict the next word or phrase that you'll type.