There used to be a time that only facts (or something similar to it) were recorded in the depositories of knowledge, however with the proliferation of the internet (and later instant messaging), people have intentionally (and unintentionally) perverted this until it's become harder to differentiate fact from fiction.
Well that's not true exactly, the truth is still relatively easy to discern via a handy-dandy search engine, or by using Snopes -- my favourite debunker of bullshit. (You can also watch the show "Penn & Teller: Bullshit!" on Showtime for some more knowledge, delivered with a humourous edge.)
However, most people (you know who you are) are too trusting &/ too lazy to check the facts for themselves. They then pass on the garbage to you, which makes you more likely to believe it to be true (if you received it from someone you think to be intelligent).