Fifty years have passed since November 22, 1963, the fateful afternoon when President John F. Kennedy was slain by an assassin's bullets in Dallas, Texas. Almost immediately after Kennedy was confirmed dead, widespread speculation and paranoia naturally engulfed the United States regarding the true culprit of arguably one of America's most horrible crimes in its long history. Such speculation is still very much alive fifty years later, as we've undoubtedly seen in the media in recent months and we will no doubt be inundated with more of it this week. What we know for certain is that at 12:30 pm on November 22, 1963, President Kennedy was riding in an open air motorcade through Dealey Plaza in Dallas with his wife Jackie, Governor John Connally of Texas and his wife Nellie when as many as three shots rang out from a nearby book depository. The first shot is widely believed to have missed the motorcade, the second went through Kennedy's upper back and allegedly exited through the throat striking the Governor, and the third and final bullet exploded Kennedy's head, as infamously seen in the Zapruder video. The only confirmed shooter to this day was 24-year-old former marine Lee Harvey Oswald, a Marxist expatriate who had defected to Soviet Russia after his discharge. Oswald was arrested later that afternoon for the murder of Officer J.D. Tippit and was arraigned for the murder of President Kennedy and Officer Tippit a short time later. However, two days later, Oswald was killed by nightclub owner and alleged mobster Jacob Rubenstein, aka Jack Ruby. After being charged with first degree murder, Ruby insisted until the day he died in prison that his sole motivation was rage over the President's death and to spare Mrs. Kennedy from returning to Dallas for a lengthy trial. In a nation with more questions than answers at this point, speculation ran rampant and some of it still remains to this day. A Gallup poll released just last week reveals that about 61% of Americans believe that there is something the American government is not telling the world about what happened to Jack Kennedy. Some theories are more popular and some even more plausible than others, leading to the establishment of the Warren Commission to conduct formal investigations into the President's assassination. Chaired by then-Chief Justice of the Supreme Court Earl Warren, the commission put forth the infamous "single-bullet" theory, which we will naturally get to later. This theory along with several other investigations led to the 889-page report in 1964 that both Oswald and Ruby had acted alone in their crimes. This ruling, however, has come under heavy criticism in the last 50 years for not being thorough enough. So, who really killed the President? That is, did Oswald and Ruby act alone without any interaction with each other after all? There are admittedly more questions than answers even today, but everybody has a different theory. We've scoured the all knowing Internet forums looking for answers, and now come to you with 20 of the most popular theories. Some are more plausible than others, while some are completely bonkers to the point where we'd want to spit our drinks all over our perfectly good LCD monitors from laughing so hard. We'll start with the more plausible ones and work our way down the evolutionary ladder.