Surfing in CS:GO is something I enjoy doing in my freetime. It is not an official gamemode but it is something the community has created as a side game. I like surfing because it helps me to relax and it is fun to compete with your friends to see who can complete each map in the quickest time. It is connects to physics because the original creators of the game did not make their physics engine in hopes that people would be able to surf. It also shows that if you didn't have friction and your legs could just slide on ramps you'd be able to a lot of crazy stuff.

The basics of surfing are:

• To surf in a straight line, strafe (a or d keys) into the side of the ramp (those things that float in the air), strafing right if you're on the left side, strafing left if you're on the right side. Think about this diagram: D/\A. Never press the back or forwards key while surfing because the forward key will make you slide off (more on the back key, s, later). Keep the mouse pointed in the direction you want to travel, the pitch of your cross hair doesn't matter, just don't look left or right if you want to go in a straight line.
  
• To turn, when you are in the air strafe in the direction you want to turn, left or right, while smoothly changing your direction with the mouse in a centripetal fashion towards that direction. When your velocity is in the desired direction, stop strafing. As soon as you hit the new ramp strafe into the side of it again.
  
• To pick up speed, start at the top of a ramp and move downwards. Make sure you do not move the mouse around too much when you are on a surf ramp then you will lose speed causing you to fall off when you get to the end or when you are surfing.
  

This is a video showing surfing.