New Concept: Code Loops

You may have noticed that this example program runs again and again- that's a code loop in action. Computers don't get tired and they don't get bored, so it's very easy to program a computer to do the same thing over and over. When your blinking LED code reaches the closing curly brace of void loop(), it jumps back to the top of the void loop and starts running again, line by line. The loop here doesn't change each time it is run and it never stops. Later, you'll learn about loops that change as they run and that stop once they reach a certain goal. 

New Concept: It's All In the Details

If you worked on the challenges in this program, you may have noticed how a small change in the code can have a big effect on how it works- or stop it from working at all! Computers are very precise, so make sure you're carefully looking over all of the parts of your program as you make changes. A misplaced comma or forgetting to change a number in the void setup() can make a big difference in how your program works!

New Concept: Speed!

When you worked on the challenge about changing the code's delay, you may have tried a really, really small number for the delay and noticed that you couldn't see the blink at all! Because computers are so precise, you can be certain that the computer ran the blink commands, even if they were too quick for you to see. Sometimes, you want a computer to run at lightning speed. Other times, you need to slow it down so that you can observe what's happening at human-speed. Use delay(); as a tool in your programs to slow things down.