There was some confusion about what Google Now really is. It is easy to describe it as the version of Google's Siri, but is in fact far more ambitious than that. Of course, you can use it to set reminders for buying milk or dinner with friends, and you can ask fundamental questions about the future of the weather or who directed The Shining, but the real attraction is its ability to anticipate your desires and needs.
If you allow Google Now to learn more about you and your habits, he can throw the information that you think might be interested. News, sports, weather, and traffic information is available in real time according to your movements and previous searches. Information is used as cards, which you can use for details or drag away to ignore. When it works, Google Now can you give what you want before you even know you want.