Grinds are tricks where you ollie onto an obstacle, or you can do a flip trick onto an obstacle, and land on either one of your two trucks on the obstacle. There's many different types of grinds, they all depend on how you land on the obstacle, so I'm going to go over some of the basic grinds. First is a 50-50; it's definitely the most basic grind you can learn. That's where you ollie up and land with both of your trucks on the rail. The next grind you can learn is a 5-0 where , instead of landing on both trucks, you just land on your back truck and slide the obstacle. After doing a 5-0, you can learn to do a nosegrind, where you ollie up and land on your front truck. Some other grinds you can learn are Smith grinds and feeble grinds. Now, a Smith grind is where you approach the obstacle, ollie up, and land with just you back truck on and your front truck hanging off to the side. Now, a feeble is where your front truck lands on the other side of the obstacle like that. That's a Smith. That's a feeble. Now, just like in skateboarding, with fingerboarding there's front side and back side. So if you approach an obstacle from this side of the rail and do a grind, that's called a front side 50-50. If you approach the obstacle from other side and do the same trick, that's called a back side 50-50. So depending on what side you start at, that determines whether or not the trick is front side or back side. And that's how you do grinds on a fingerboard.