Amazon (NASDAQ: AMZN) CEO Jeff Bezos spoke about the future of his company in his annual investor letter, which was released earlier this month. You can read some of the biggest takeaways here, but let's focus for a moment on the section that was almost entirely devoted to the artificial intelligence subcategory called machine learning. Machine learning is when a computer, or program, learns how to use information on its own, without having to be expressly taught how.