I remember inline skating as a kid at the skating ring. I use to love going there.
I've done it once or twice in my life. Never was so good at it, lol. Inline skating is a sport that's practiced widely internationally 
It is, they have it at the Olympics and those guys are crazy good at it.
No kidding. I expect so if they made it there! Inline skating is when you have 2 to 5 wheels in a single line under a boot
So if that is inline skating then what are the skates called that have 4 wheels and that little knob to help you stop that most kids use?
I'm not entirely sure, but I suppose it's called a skate guard. The inline design allows for greater speed than roller skates
Yeah I always liked the "Big kid" skates at the skating ring because you could go faster.
Sometimes too fast if you aren't very coordinated. Great risk of injury lol. Inline skating is also called roller blading