The inability to understand or even recognize that others may have different experiences than us, based on how they look, who they are or the circumstances in which they live, is what constitutes unearned privilege. It's how a relatively wealthy white male student at Princeton can come forward and proclaim he won't apologize for his privilege.
He just doesn't see it; he doesn't really believe that it's there. And plenty of people don't.
All of us, to some degree, have a kind of privilege, though some of us have more leverage with our privilege than others. In any case, it's important to recognize what our privilege is, especially if we're going to do something about it.
YouTube star Franchesca Ramsey and animator Kat Blaque made a cute and very accessible video using the animal kingdom to show what privilege is and how it works. A snail tries to get under a fence, just as her caterpillar buddy does, but can't fit. The caterpillar is impatient, doesn't want to make accommodations, can't believe the hold up!