Slides and Grinds involve getting the board up on some type of ledge, rail, or coping and sliding or grinding along the board or trucks, respectively. When it is primarily the board which is contacting the edge, it's called a slide; when it's the truck, it is a grind. Grinding and sliding skateboards started with sliding the board on parking blocks and curbs, then extended to using the coping on swimming pools, then stairway handrails, and has now been expanded to include almost every possible type of edge.
░▒▓█~Kiki's Club House~█▓▒░
