A UFO is any unidentified flying object. If you saw a strange looking aircraft in the air and could not tell what it was, it would be a UFO. In the context of your question, though, I assume you mean vehicles used by other life forms from elsewhere in the universe.
There have been many, many reports of UFO sightings, many of which were investigated and easily identified as everything from balloons to strange birds or aircrafts.
There have also been many reported sightings of UFOs presumably used as vehicles used for travelling by other life forms in the universe. Most of these were and still are unidentified and those that may be actual sightings of space aliens have been kept as confidential information by various governments to prevent public fear and panic.
UFOs are very often seen on Earth, and nobody knows what is inside of one. If there are truly UFOs from space, when they supposedly come to Earth they may already be learning from us.
UFOs have been reported in virtually all of the states at one time or another.
Some people believe that spaceships from other planets have visited Earth, but no one has ever been able to prove it.
No they don't, and you ever tells you they do are lying
yes
Yes, they came to earth on 24/7/09 because i am from Pluto
Depends what you mean by UFOs. If you mean 'spaceships with little green men' nobody has proved that such visits have ever taken place, and indeed, given the vastness of space, it is unlikely that they ever will. Some strange visual phenomena have been observed for which there is no explanation as yet; by their very nature no explanation for them exists.
The subject of aliens and UFOs have been getting more coverage by mainstream media than ever before.
Since no humans have visited Mars, it is unsure. But Mars is often mistaken for UFOs because of how bright the planet is.
UFOs The Best Evidence Ever Caught on Tape - 1997 TV was released on: USA: 28 July 1997
No.
I think you mean "Has the Earth ever been photographed from outer space?" and yes it has.