What are UFOs?
UFO stands for unidentified flying object. So technically anything that you saw flying and could not identify is a UFO. That said the term UFO has come to mean ETV in most people's minds. What is an ETV? An ETV is an extraterrestrial vehicle. In other words a vehicle from "somewhere else". (Hint: they mean space)
Most people believe that the UFOs that everyone is on about are spaceships from another world. Most people believe this but don't like to think about it too much, in case this reality becomes too real. A bit like the way many people believe in ghosts. They know that they are probably real but don't know much about them and hope that they never have to know much about them. The rest of the world think that people who have seen UFOs or claim to be abducted are crackpots and nuts.
These UFOs have taken various forms from saucer-shaped to cigar-shaped. This is no surprise since they come from different areas of space and are belong to different races. Some of the best video and photos of them have come from the military in various different countries.
The trouble with getting good evidence is that there are numerous hoaxers who for reasons best known to themselves keep muddying the waters of the UFO phenomenon. Some of these hoaxers may be deliberately undermining the credibility of genuine witnesses because they have their own agendas or some may simply be doing it for fun. Either way they do quite a bit of damage with their false reports and doctored images.
So far there is no undeniable proof that they exist, whatever they are. However the number of people who have seen them and the number of abduction claims is rising every year despite the ridicule that these people are subjected to.
But, remember this. The world was once flat. What will the people of the future think when they are told that we once thought we were alone in the whole of creation?