A flying saucer is a shape of an object that people believe might be seen in the sky. It is called a saucer because it looks similar to the shape of a cup or a plate that you use to eat from.
People often say that these objects are from outer space. That they're spaceships that come from other planets.
However, all of these statements are mainly just people's opinions, and no scientific evidence has proven the existence of flying saucers or aliens.
Sometimes, people see flying saucers when they're flying their own airplanes or helicopters. These objects could be anything from a balloon or a bird to an airplane that's flying strangely. It's also possible that people just see strange things and think they're seeing a flying saucer.
So, while some people believe that flying saucers are from outer space, the truth is that there is no real evidence to support that theory.