Errors are mistakes in a program that cause it to stop working correctly or behave in an unexpected way.
Every JavaScript developer faces errors — from beginners to professionals. The difference is that experienced developers know how to identify and fix them quickly.
Understanding the types of errors in JavaScript is the first step toward becoming confident in debugging.
Main Types of Errors in JavaScript
- Syntax Errors
Happen when code is written incorrectly. - Runtime Errors
Happen while the program is running. - Logical Errors
Happen when code runs but gives wrong results.
Knowing these error types helps you find problems faster.
Syntax errors happen when JavaScript cannot understand your code.
They must be fixed before the program can run.
Here, the program crashes while running because it tries to access a property of null.
These errors appear only when the code executes.
These examples show how different types of errors appear in JavaScript.
By learning to identify syntax, runtime, and logical errors, students gain the foundation needed to debug confidently and write reliable, professional code.