WEBVTT 00:00:13.010 --> 00:00:15.680 This lesson is called songwriting with parameters. 00:00:15.680 --> 00:00:18.350 We're going to be writing some songs here. 00:00:18.350 --> 00:00:21.960 Sometimes the chorus is just a little bit different each time you sing it. 00:00:21.960 --> 00:00:25.230 Do you remember Old Macdonald Had a Farm? 00:00:25.230 --> 00:00:27.350 The chorus is slightly different for each animal. 00:00:27.350 --> 00:00:32.870 And on that farm, he had a cow, e-i-e-i-o. 00:00:32.870 --> 00:00:40.190 The small change in each chorus can be shown using something we call parameters. 00:00:40.190 --> 00:00:42.280 Sometimes a function needs a parameter. 00:00:42.280 --> 00:00:46.900 A parameter is an extra piece of information you can pass to a function to customize it 00:00:46.900 --> 00:00:48.590 for a special need. 00:00:48.590 --> 00:00:53.760 When you make ice cream sundaes with your friends, you are using a process similar to 00:00:53.760 --> 00:00:56.550 parameters in a computer program. 00:00:56.550 --> 00:01:00.800 The disk of vanilla ice cream might be the same for every sundae but when you ask your 00:01:00.800 --> 00:01:06.290 friends which two toppings they'd like, you could get lots of different combinations. 00:01:06.290 --> 00:01:10.760 Topping is the function name but each type of topping is a parameter. 00:01:10.760 --> 00:01:15.780 Functions and parameters work together to make great computer programs and great sundaes 00:01:15.780 --> 00:01:15.940 too.