Always get these 2 terms mixed up. But my friend just got there basement and carport cemented/concreted in. (before it was dirt) and I was wondering something. How do you get the different surface "texture" (ie fine grit or coarse grit finish) like a carport or wharehouse floor which is smooth as can be. And a regular slab of cement/concrete for sidewalks, etc. How do they get it really smooth, and semi-smooth from it being really rough to start off with? Do they use more sand and less gravel? Thanks Also just so I don't sound like an idiot, whats the difference between cement and concrete?