One night this January, as Robert Stewart scrolled through old Hinge matches, he decided to revive a conversation he had begun months ago with a woman on the dating app. After picking up where they left off and exchanging a few pleasantries, Stewart asked if the woman wanted to get on a phone call. He hoped it would lead to an in-person date. "We could do that," the woman answered, but with one caveat. Stewart, who lives in Dallas, clicked on a Google Form the woman sent, titled "Dating Compatibility Q&A".

August 2, 2017 --C-3PO's fluency in more than 6 million forms of communication in "Star Wars" set a high bar for human-robot interaction, and the field has been struggling to catch up ever since. They started in the factories, taking over physically demanding and repetitive tasks. Now robots are moving into hospitals, shopping malls, even the International Space Station, and experts don't expect their expansion into human spaces to slow down anytime soon. "Even 10 years ago, the primary use of the robots was in the dangerous, dirty, and dull work," says Julie Shah, an engineering professor at the Massachusetts Institute of Technology in Cambridge, Mass. "You'd deploy them to operate remotely from people, but [now] robots are integrating into all aspects of our lives relatively quickly."

Imagine a robot stacking boxes in a warehouse when it suddenly sees that one box is in the wrong stack. It goes back and puts the container in the right place. How did the machine know it had made a mistake? The robot's human boss didn't punch any codes into a computer to have the robot correct its mistake. The boss didn't say a word.