Netflix is uses machine learning to give you personal recommendations of content to watch; Amazon uses machine learning to recommend products to buy based on what you've already bought. These are the so-called recommenders. They are usually (but not only) built using clustering techniques.
Machine learning techniques have been also used to diagnose illnesses. Aside from the application of clustering in cancer diagnosis already mentioned in Chapter 4, KDD, Data Mining, and Text Mining, neural networks can be trained to read various exams and even predict how likely a patient is to develop certain kinds of diseases—this field is called predictive medicine and highly benefits from machine learning advancements.
