A Kind of A.I. Called Machine Learning Is Reshaping How We Live. It's Time We Understood It.

While machine learning originated as a subfield of artificial intelligence--the area of computer science dedicated to creating humanlike intelligence in computers--it's expanded beyond the boundaries of A.I. into data science and expert systems. But machine learning is fundamentally different from much of what we think of as programming. When we think of a computer program (or the algorithm a program implements), we generally think of a human engineer giving a set of instructions to a computer, telling it how to handle certain inputs that will generate certain outputs. The state maintained by the program changes over time--a Web browser keeps track of which pages it's displaying and responds to user input by (ideally) reacting in a determinate and predictable fashion--but the logic of the program is essentially described by the code written by the human. Machine learning, in many of its forms, is about building programs that themselves build programs.