Sine is based on a right triangle. It is calculated by choosing an angle, and dividing the side opposite that angle by the triangle's hypotenuse. Sine is ratio between -1 and 1. When you use Sine in Hopscotch, it comes in an equation that magnifies the value of Sine, since -1 to 1 is a very small number.
Search the community for sine and cosine to see examples of cool visuals. Or check out our video on how to use Sine!