Drone basically is an unmanned air vehicle fitted with weapons for target destruction. But they can be spotted via Radars anytime. Stealth Drone basically works the same as drone but it is hidden from the Radar. Radars can't spot the stealth plane. Now, the thought of the hour is "Why do they need Stealth Drones in Afghanistan When Afghanis don't own a Radar system?". Is this for Pakistan? Is it?
The air force said the aircraft came out of Lockheed Martin's "Skunk Works," also known as Advanced Development Programs, in California - the home of sophisticated and often secret defense projects including the U-2 spy plane, the F-22 fighter jet and the F-117 Nighthawk.According to DEBKAfile’s military and intelligence sources, Washington had a reason for letting the Beast surface at this time in the form of a published photograph and a note about its ability to fly over the borders of Iran, China, India and Pakistan for collecting “useful data about missile tests, telemetry, signals and multi-spectral intelligence. The disclosure came on the heels of Iran’s big air defense exercise for guarding its nuclear sites which ended in the third week of November; it appears to be a message to Tehran that all its war games, especially in intelligence and electronic warfare, were pointless since its skies are wide open to American drone activity against which Iran has no recourse.
Read the confirmation report on Asia One