Much like DC Comics' Legion of Super-Heroes, Marvel's X-Men can seem a bit impenetrable. Readers have to contend not only with the team's nearly 52-year history -- minus that five-year period when no new stories were published -- but also multiple titles, alternate universes and recons. Y'know, the usual stuff.
Luckily, IGN has produced "Every X-Man Ever," a nearly 11-and-a-half-minute video infographic that is billed as "detailing everyone who ever joined Professor Xavier's team of X-Men." Naturally, that's your cue to interject with, "But they forgot ..."
If you prefer a text version, IGN has that too.