An introduction to the heroes, allies and villains of 'The Avengers'

Who are "The Avengers"? Chances are, if you've been to the movies at all in the last couple of years, you've seen at least one of these characters before. The Avengers have a long history of appearances in comic books and other media. This particular version, however, is the culmination of the last few years of Marvel Studios films, which tie each separate story into one giant team-up. But you might not be familiar with all of the connections. So here's a brief introduction to each of Earth's Mightiest Heroes, along with their support staff and enemies. Read on, true believers!