Spam is always annoying, but it can occasionally be disastrous. Google has now deployed its artificial neural network to stop more of it from arriving in your Gmail inbox, something it hinted at earlier. It's designed to "detect and block the especially sneaky spam -- the kind that could actually pass for wanted mail," according to the company. The system also uses machine learning to track your usage patterns and figure out if you want certain kinds of mail, like newsletters or promos. Most critically, Google said that Gmail is now better at catching impersonation -- when emails appear to be from a known contact, but were sent by someone who is definitely not your friend.