Unmanned describes a vehicle, machine, or facility that operates without people on board or present to control it. An unmanned spacecraft travels through space with no astronauts inside, controlled instead by computers or by people on Earth sending radio signals. An unmanned drone flies through the sky with cameras and sensors but no pilot sitting in a cockpit.

The word appears frequently in discussions of exploration and military technology. Scientists send unmanned probes to Mars because the journey is too dangerous or expensive for human astronauts. These spacecraft take photographs, collect samples, and send data back to Earth while being controlled remotely, sometimes from millions of miles away.

While unmanned remains the most common term, you might also hear people say uncrewed or autonomous, especially when describing vehicles that drive, fly, or navigate themselves using artificial intelligence rather than remote control. An unmanned store operates without cashiers or staff, using cameras and sensors to track what customers purchase.

The technology keeps improving. What once required a human operator can now often be handled by sophisticated computers and sensors, allowing us to explore dangerous places, from the deep ocean to distant planets, without risking human lives.