Big data is often talked about but not well understood, as people claim expertise in it without truly knowing how to work with it, similar to how teenagers talk about sex. The document provides examples of using big data to predict things like driving behaviors, salary from job posts, when someone might quit something, and errors from typed code. It also lists examples of matching people on dating apps and creating sports prediction apps. The document discusses sponsoring a program to train 10 capable young data scientists.