Who doesn't love a good conspiracy theory?
The Moon landings, the JFK Assassination, Roswell and the Illuminati are all topics for debate on the Internet - and you'll encounter some interesting explanations.
More recently we have been inundated with speculation that the world is going to end - which always turns out to be a hoax.
If you remain unconvinced that conspiracy theories aren't all they are cracked up to be, then you'll be pleased to hear that some actually are real.
Over on Reddit, users have been listing conspiracies that are now accepted as being true.
Here are some of the best:
1. The FBI spied on Ernest Hemingway
2. Project MKUltra
3. Lance Armstrong
4. 2008 housing market collapse
5. The FBI spied on Martin Luther King Jr
6. Ed Snowden
7. Father Christmas (sorry kids)
8. CIA importing cocaine
9. RMS Lusitania
11. The Gulf of Tonkin incident
12. Governments using bots