Lesson 17 of 20
Error Handling
Recover from expected failures.
Introduction
Errors can come from invalid input, unavailable services or programming mistakes. throw creates an error and catch handles it.
Good error messages help users recover and help developers diagnose problems.
Key insight
Recover from expected failures.
Example
try {
throw new Error("Something went wrong");
} catch (error) {
console.log(error.message);
}This example shows the core error handling idea in a small, runnable program.
Real-world example
Forms show validation errors while network failures offer a retry action.
Test yourself
2-question check
1
What is the main idea in Error Handling?
2
Where can error handling be useful?
Ready to check your understanding?
Answer every question, then submit your quiz.
Try it yourself
JavaScript compiler
Runs in your browser. Nothing is sent to a server.
Output appears here
Practice challenge
Catch invalid JSON with JSON.parse.