How long it takes computers to brute force a password. Brute force means just trying every combination.
Most password crackers are smarter than this but I always have a hard time explaining to people why they shouldn't use the name of their dog plus a number or an exclamation point. We need a simple image to explain how modern password crackers work.
I would also really be interested to see a video of how this table has changed every year since, say, 1980.