A function is just a subprogram that you can make by indenting your program after an arrow
->. If you name your functions with a definition like
smiley = ->, you can use your function anywhere with
do smiley. If you move the turtle, you can make a page with several smileys.
You can define different functions to help make a richer scene. Can you customize your smiley function to give it a specific personality? Can you functions for other characters?