"...Illinois is an employment-at-will state..."

I didn't know there was any other kind of state. Would anyone care to explain what happens in a place where "employment-at-will" is not the rule?

By the way, the technicalities that John in Kansas so carefully explains may be true, but they don't apply to the majority of employees. Most of us don't work for the government, don't belong to a union, and don't have contracts.