Nowhere is this variation more consequential than in the category of one-way attack drones: systems designed not to return home like an airplane, but to fly directly into a target and destroy it, like a bullet or a missile.

An artist’s impression of Shahed-136 drones swarming an airport. Credit: Wikimedia Commons. Wars in Ukraine and the Middle East have propelled drones into the headlines. The word “drone” now stretches to cover everything from hobbyist camera rigs available on Amazon to the Predator and Reaper systems the United States has relied on to fight terrorist organizations over the past 20 years.

Ukraine’s Air Force reports that Russia conducted a large-scale combined attack on 15 April, with missiles and drones targeting multiple oblasts and strikes recorded at several locations.

Germany delivered 15,000 Strilla interceptor drones to Ukraine's National Guard. Here's how the rocket-boosted quadcopter works and why it matters.

Unlike ballistic missiles, attack drones can be produced and launched with little infrastructure, making them difficult targets.