colour = "blue" // blue is the actual value, and a string, so quotes
size = 5 // 5 is an integer, so no quotes
SetLinkColour (colour) // colour is a holder for the string value, no quotes
SetLinkColour ("blue")
ball.colour = colour
ball.colour = "Blue"
SetLinkSize (size)
SetLinkSize (5)
ball.size = size
ball.size = 5