A UFO is an unidentified flying object. I saw one of those once. Big and shiny with lots of flashing lights. Luckily I was wearing my tinfoil hat so everything was okay. My uncle once saw a UFO, but he has also been struck by lightning twice and tries to pay me in horses when I work for him. I suspect that his horse Yorvic was present when he saw the UFO, so you could probably ask him. He’s more believable than my uncle.