Course 3 - Artist - Functions explained by Bill Gates

One of the great things in computer programming
is once you've taught a computer how to do

an action, you can call that function again.
You give it a name and then you can call it.

That's really like extending the language.
In the program we built, we learned how to

draw a square by moving and turning four times.
We can take that function and give it a name,

draw a square, so that any time we want to
do that, we simply say draw a square and it

will go back and invoke that function, that
code. It will get done for us. We've added

that concept to our programming language.