Corporation catalogue
EVE Online corporation lookup
Who they are, who they fly for and where they flew before.
Which corporations are here
EVE has around half a million corporations and most of them are one-pilot shells opened for a hangar. Listing all of them would be half a million pages about nobody, so this catalogue keeps two kinds: corporations that belong to an alliance - someone is paying their bills - and corporations that show up in killmails, which means someone is actually flying them.
That is also what the activity label means. It is not guessed from headcount: a corporation with a hundred accounts can sit dead for a year, while a two-pilot one flies every night.
What a corporation page answers
Pilot count, alliance, CEO, tax rate and founding date - and the full alliance history, which the game servers hand out reaching back to the day the corporation was founded. That last one is the piece that is hard to find elsewhere: it says who they used to fly with, and when they left.