What is a Bug?: Introducing Errors in Code

Learning Objectives Define the term 'bug' in the context of computer programming. Identify a syntax error in a simple program. Identify a logic error in a simple program. Explain the difference between a syntax error and a logic error using a simple analogy. Use an error message as a clue to find a bug. Test a program with simple inputs to check for logic errors. Have you ever followed a recipe perfectly, but the cookies still came out weird? 🍪 Computers can make mistakes like that too when our instructions aren't quite right! In this lesson, we'll learn about 'bugs,' which are mistakes in our code. We will discover different types of bugs and become super-sleuths who can find and fix them, making our programs work perfectly. Real-World Appli...

TermDefinitionExample BugA mistake or error in a computer program that causes it to do something unexpected or wrong.You tell a character to move forward 10 steps, but it moves backward instead. That's a bug! Syntax ErrorA 'typo' or grammar mistake in the code that the computer doesn't understand. The program usually won't run at all.Writing `move_forword(10)` instead of `move_forward(10)`. The computer doesn't know the word 'forword'. Logic ErrorA mistake in the program's thinking. The code runs, but it doesn't do the right thing you wanted it to do.You want to add two numbers, but you accidentally use the minus sign. The program gives an answer, but it's the wrong one. DebuggingThe process of finding and fixing bugs in a program. It...

Read the Error Message When the program crashes or shows an error, carefully read the message it gives you. Use this rule for syntax errors. The computer often tells you the line number and the type of mistake it found, which is the best first clue for debugging. Test with Simple Inputs Check your program with easy, predictable inputs to see if you get the expected output. Use this rule to find logic errors. If you have a calculator program, test it with `2 + 2`. If you don't get 4, you know there's a logic bug somewhere. Trace the Code Read your code one line at a time, pretending you are the computer, and write down what happens to your variables. This is a powerful way to find logic errors. By following the instructions exactly as they are written, you c...