This has already been stated above, but the key is the severity. I destroyed my ankle...doing some stupid little hop thing off of the fourth stair from the ground outside of my apartment complex when I lived in California. There was a group of like six really good looking young women congregating out on the parking lot, right below my apartment and the stairs.
So I jauntily stride out of my apartment, straining with effort in my attempt to convey total coolness and general apathy...making sure to light my Parliament in what I'm sure was just the most super suave way ever, then to the stairs. On the fourth stair I jumped...and somehow managed to bend my ankle back far enough on the landing that I heard two pops. RIGHT IN FRONT OF THE CUTE GIRLS. Who, God bless 'em, couldn't help but start laughing hysterically at first as I writhed around in pain. That's how you impress the ladies, guys.
Anyways, I had a pretty bad sprain. I was on crutches for 4 or 5 days, but then it got markedly better pretty quickly. I was playing basketball within 10-14 days or so and my ankle was really swollen at first, swollen enought that on first look the ER nurse said she thought I had probably broken something. Sprained ankles suck, but it just depends on the person and the type of sprain. Mine was lower ankle. High ankle sprains can be more troublesome, I think.