Ghosts, the paranormal and the supernatural have always been debated. Do they exist?
Many people have reported sightings before, but without any real proof, they're usually disregarded as merely stories. Being able to take photos of spirits obviously helps the cause, but are all of them real or have some been doctored?
Here is a round-up of 24 of the most famous "ghost" photos of all-time. Some have been faked no doubt, but they look so good on first inspection they could definitely convert some non-believers.
William Mumbler - 1860s
William Mumbler is credited with creating the first photo to show a ghost in the 1860s. But it wasn't a ghost at all, it was simply an accidental case of double exposing a negative while taking photograph of himself. The entrepreneur in him turned this into a business, where members of the public would have their portrait exposed with an image of a dead relative.
Lord Combermere - 1891
This image taken of the library at Combermere Abbey in Cheshire, England by Sybell Corbett clearly shows a figure sitting in the chair on the left. It's believed to be the ghost of Lord Combermere, a British cavalry commander in the 1800s.
Goddard's Squadron - Freddy Jackson - 1919
This image was taken by Sir Victor Goddard, of his squadron in 1919. The ghostly image behind the fourth sailor from the left, at the top, is believed to be of Freddy Jackson. Jackson died a few days before the photo was taken by walking into a moving propeller.
The SS Watertown - 1924
This image taken from the SS Watertown shows the faces of two crewmen, James Courtney and Michael Meehan in the water. The two men died while onboard the ship and were given a burial at sea.
Other crew members on the ship saw the faces in the water but didn't initially take photos, they went back to a similar spot and saw them again. Five of the six photos showed nothing, but this was the sixth and clearly shows the faces of two men.
The Brown Lady - 1936
This photo of "The Brown Lady" is considered by many to be actual photographic evidence of ghosts. It was taken at Raynham Hall in Norfolk, England in 1936. There had allegedly been many sightings of the figure before this photo and it's said to be the ghost of Lady Townshend. She was locked in a room in the hall by her husband when he found out about her infidelity and left there to die.
Mrs Andrews baby - 1947
This photo of a child appearing over a grave was taken by Mrs Andrews in 1947. She noticed the ghost when she had the film developed, but said it wasn't her daughter in the picture. Despite there being some graves for children nearby, the child in the picture has never been identified.
An unexpected guest - 1950s
This image, taken at some point in the 1950s shows a small family sitting at a table. Two boys sit happily on their mother's laps but a pretty terrifying and unexpected guest has also dropped in. Hanging disturbingly from the rafters.
Corroboree Rock - 1959
Nobody knows who the ghostly figure in this photo is, but it was taken in Alice Springs, Northern Territory, Australia in 1959. Some people think it's just a case of a double exposure, while others think it could be a spirit watching us, or something else, because it looks like they're holding binoculars.
The Back Seat Ghost - March 1959
This photo was taken by Mabel Chinnery in 1959. It shows her husband in his car with, allegedly, her dead mother-in-law on the back seat. While paranormalists believe it to be real, others have debunked it as being another case of double exposure.
Newby Church - 1963
Some analysts think this photo taken at Newby Church in North Yorkshire, England is a fake because the character looks to be posing too much. However, Reverend KF Lord insists there was nothing visible to the naked eye when he took the photo, and photo experts say it hasn't been double exposed.
Tulip Staircase Ghost - 1966
This photo taken inside the National Maritime Museum in Greenwich, England, clearly shows a ghostly figure holding the handrail of the Tulip Staircase. Photo experts have all agreed that it hasn't been tampered with, so is considered a genuine example of ghosts' existence.
Robert A Ferguson - November 1968
Because this photo was taken on a Polaroid, it's been deemed by many to be legitimate. It shows Robert A Ferguson giving a speech, with the ghost of his deceased brother Walter peering over him.
Worstead Church - 1975
Peter Berthelot took this picture of his wife, Diane, sitting on a pew at the Worstead Church in Norfolk, England in 1975. When they had the film developed, they noticed a ghost sitting on the pew behind Diane. A man allegedly stayed in the church all night sometime in 1830 to try and disprove the theory of ghosts, but he claimed the following morning he had in fact seen the white lady seen in this picture.
Amityville Ghost - 1976
This photo, taken by Ed and Lorraine Warren, claims to show the ghost of nine-year-old John DeFeo. DeFeo, along with his other brother, two sisters and parents, were killed by his older brother Ronald at their house in Amityville.
Ed and Lorraine Warren were paranormal experts who entered the house and captured this image using a camera that consistently took infrared photos during the night.
The DeFeo murders were the inspiration for The Amityville Horror books and films.
Toys 'R' Us - 1978
The Toys 'R' Us store in Sunnyvale, California is allegedly haunted by the ghost of Johnny Johnson, and this image shows a silhouette leaning up against the shelves. The same figure wasn't there when the photo was taken.
The story goes that Johnny had a thing for a girl named Elizabeth, the daughter of a plantation owner - the plantation used to be on the Toys 'R' Us site. Johnny bled to death after cutting himself chopping wood, and now roams the aisles of the store searching for her. Or Teenage Mutant Ninja Turtles.
St Botolph's Church - 1982
If you look carefully in the upper right-hand corner of this photo, you can just make out a translucent figure. It was taken at St Boltoph's Church in 1982 and, at the time, there were only three people in the building. A builder later contacted Chris Brackley, who took the photo, to tell him he recognised the face as being the same as someone he'd previously seen in a coffin in the church.
Coventry Spectre - 1985
At first glance, you'd think there's nothing wrong with this photo. But look again, and you'll see a tall, dark figure wearing what could be a monk's frock, with a hood, in the top left. This is a photo of the Coventry Freeman society showing everyone at the event, including the mysterious figure, bowing their heads. Nobody at the event was seen wearing that style of clothing.
The ghost pilot
In 1987, Mrs Sayer was visiting air airfield in England with her friend. She thought it would fun to take a photo of her sitting in the cockpit.
When the image was developed, there was a man sitting in the pilot's seat who hadn't been there when the photo was taken. A long lost pilot? No one is sure.
Pawling Fire Department - 1988
The white figure in this photo is believed to be some sort of angel, overlooking Rose Benvenuto, who was involved in the car crash. She said it could only have taken a miracle for her to survive the crash, and lo and behold, there's an angel-like figure in attending firefighter Sharon Boo's photo.
Madonna of Bachelor's Grove - 1991
The Ghost Research Society of America took this photo at Bachelor's Cemetery in Illinois, after it noticed strange readings on its equipment. Researchers didn't see anything at the time, but when this image was exposed, it showed a woman in white clothing sitting on one of the graves.
The Wem Town Hall Ghost - November 1995
Although Tony O'Rahilly's photo appears to show the ghost of a young girl in the doorway to a burning down Wem Town Hall, it was later deemed to be a fake. The girl in question apparently appears on a postcard that appeared in the local paper.
Boot Hill Ghost - 1996
Only Ike Canton's friend was seen when this photo was taken, The mysterious man wearing a hat behind him wasn't. Canton later looked more closely at the photo and decided the figure was, in fact, holding a knife, with the point ending just above his collar.
Grandpa's Ghost - August 1997
Denise Russell took this photo of her grandma, who lived alone at the time, on 17 August 1997. Even though the photo had been developed, copied and given to other family members, nobody noticed the male figure standing over her until Christmas Day 2000. The Russell family say it's a spitting image of their grandpa who died in 1984.
Sefton Church - 1999
This picture at Sefton Church in Liverpool, England, clearly shows a man wearing a black uniform, believed to be the old church minister. There were allegedly only two photographers in the church on the day it was taken, and neither of them recall seeing a physical being standing there when the photo was taken.
Girls in Manila - 2000's
The two girls in this photo, taken in Manila, Philippines, didn't report seeing anyone or feeling any presence when this photo was taken. It was also taken on a digital camera, so it can't have been the result of double exposure.
Waverly Hills Sanatorium - 2006
This image was snapped in an abandoned tuberculosis hospital in Louisville, Kentucky in 2006. As you can imagine, in its heyday, the hospital saw an incredible amount of sickness and death - leading many to believe in the possibility that it could be haunted.
In recent years, it has become one of America's most popular destinations for ghost-hunters.
This eerie image apparently depicts Mary Lee, a nurse who hung herself in the hospital. The story goes that this poor woman was impregnated by a doctor who worked in the hospital but later wanted nothing to do with her.
Tewin Bury Farm Ghost - 2008
Neil Sandwich took this photo of a farmhouse where his friends were getting married. When he put the photo into Photoshop and adjusted the exposure, he noticed a mysterious white figure on the right-hand side, appearing to be peering out of a doorway. Cleaners at the farmhouse had apparently seen the ghost of a young boy wearing white clothes before, too.
San Antonio crossing ghosts
Years ago, sometime in the 1930s, it's said that a school bus full of children broke down near a railway crossing in San Antonio, Texas. Tragically, a speeding train hit the bus, killing several children and the bus driver.
This photo taken by Andy and Debi Chesney appears to show some ghostly apparitions that people have suggested look like ghosts of the children. Like any of these images, there is some debate about whether they're real and even if the history itself is true, but they're still spooky.