Lesson 9 of 20 · Fix It!

Fix It! — Part 9

Find what's wrong and fix it.

What you'll learn

You will learn to read code carefully to find mistakes (bugs) and understand how to fix them.

Words to know

Bug: A mistake in the code that makes the program do something wrong or unexpected.
Debug: To find and fix bugs. You look at the code and the output to figure out what's wrong.
Fix: To change the code so it works correctly. Fixing bugs is part of coding.

Your turn

📋 Show the steps

Press ▶ Run and see what the computer says!

1Read the code line by line: x is 2, y is 3, z is x + y which is 5. The output would be 'Total: 5'. This code is correct!
2Now imagine the last line was print('Total:', x) by mistake. It would show 'Total: 2' — wrong! That's a bug.
3Debugging means reading code carefully, finding where it goes wrong, and fixing it. It's like being a detective!
4Every coder — even experts — writes bugs. The skill isn't avoiding bugs, it's being good at finding and fixing them!

Auto-run is on: change the code and the result updates by itself.

Auto-run

Output

Loading Python... This may take a few seconds.

Check your understanding · 1 of 5

What is debugging?

Check your understanding · 2 of 5

print("Hello) What's the bug?

Check your understanding · 3 of 5

How do you find a bug?

Check your understanding · 4 of 5

x = 5 y = 0 print(x + z) What's the bug?

Check your understanding · 5 of 5

What is a bug in code?

Nice work!

You got 0 of 5 right.