0:00:04.059,0:00:10.840 One of the great things in computer programming[br]is once you've taught a computer how to do 0:00:10.840,0:00:22.390 an action, you can call that function again.[br]You give it a name and then you can call it. 0:00:22.390,0:00:28.960 That's really like extending the language.[br]In the program we built, we learned how to 0:00:28.960,0:00:39.250 draw a square by moving and turning four times.[br]We can take that function and give it a name, 0:00:39.250,0:00:46.430 draw a square so that any time we want to[br]do that, we simply say draw a square and it 0:00:46.430,0:00:53.990 will go back and invoke that function, that[br]code and it will get done for us. We've added 0:00:53.990,0:01:00.580 that concept to our programming language.[br]In this puzzle, we have already created a 0:01:00.580,0:01:06.210 draw a square function for you. You'll see[br]it in the toolbox as a green block. What you'll 0:01:06.210,0:01:10.299 need to do is write the same code you wrote[br]before to draw a square and put it in this 0:01:10.299,0:01:16.820 function. To do that, click on the edit option[br]in the green draw a square block. This will 0:01:16.820,0:01:21.499 open up the function editor. The function[br]editor has three parts. A place where you 0:01:21.499,0:01:26.950 name your function. This will appear on the[br]green block before that function. Then write 0:01:26.950,0:01:31.960 out a short description of what your function[br]is supposed to do. In this case, it's supposed 0:01:31.960,0:01:37.229 to draw a square. The white space below this[br]is the work space and works just like the 0:01:37.229,0:01:42.149 work space you've already been using. Drag[br]and drop blocks from the toolbox into this 0:01:42.149,0:01:46.810 work space. Remember to put the blocks that[br]create a square inside the green wrapping 0:01:46.810,0:01:52.159 block for the function. Once you're done,[br]click on save and exit. This will take you 0:01:52.159,0:01:57.209 back to the main puzzle work space. Now you[br]can use the draw the square function block 0:01:57.209,0:01:59.459 just like any other block to solve the puzzle.