Almost all events that occur have a legitimate explanation as to why they happened. Events such as a man walking on the moon, and the deadly tsunami that occurred in 2004 have explanations to their cause that the majority of people accept. There are however people that do not believe the accounts given for many major events. These people, referred to as conspiracy theorists, believe that there are too many discrepancies and questions left unanswered in the official explanation of many of the major events that have occurred throughout history, and their speculations are called conspiracy theories. There are vast amounts of conspiracy theories, which range from somewhat plausible to absolutely outrageous.

A conspiracy theory is basically a hypothesis or speculation that people in a position of power have secret agreements to commit wrongful acts which will produce a favorable result for them. Conspiracy theorists tend to question higher authorities such as the government. There are many well known conspiracy theories ranging from the assassination of John F. Kennedy to a UFO being recovered in Roswell, New Mexico. The following are some of the most popular conspiracy theories throughout history.

• Moon Landing Hoax – Conspiracy theorists believe that NASA, and possibly members from other organizations faked an astronaut landing on the moon. Theorists say that there were various issues found when the photos of the landing on the moon were closely examined.

• UFO Recovered in Roswell, New Mexico – In 1947 in Roswell the United States military stated that what was recovered in Roswell was not a UFO but simply a top-secret research balloon that had crashed. On the other hand,, some people have concluded that at least one craft containing aliens had crashed, and that the aliens, some of which were possibly still alive were recovered, and there was a massive cover-up of the event.

• Assassination of John F. Kennedy – President John F. Kennedy was assassinated on November 22, 1963 in Dallas Texas while riding in a presidential motorcade. Lee Harvey Oswald was found guilty of the assassination of president Kennedy however there are many theories surrounding the presidents death. These theories include the ideas that Kennedy may have been assassinated by members of the Central Intelligence Agency (CIA), the Federal Bureau of Investigation (FBI), or various other government sectors.

• Pearl Harbor – Many theorists believe that the bombing on Pearl Harbor was provoked by president Roosevelt, that he knew of the attack ahead of time, and then covered up his failure to warn commanders.

While conspiracy theories have been around for a long time, it wasn't until the introduction of the internet in the early 1990's that the conspiracy theory community began to drastically grow. The internet is arguably the biggest aid in the spread of conspiracy theories. Conspiracy theories are likely to continue developing, and with time those theories are likely to evolve and possible become more elaborate.

Who Rules America? - A great explanation of the problems with conspiratorial views

Best Conspiracy Theories - Some of the weirdest, best conspiracy theories floating around

History's Greatest Conspiracy Theories - A picture gallery of some of the greatest conspiracies throughout history

Conspiracy Theory Origins - An in-depth explanation of conspiracy theories, and where they originated from