Errors In Javascript

1. ReferenceError:

This error occurs when you try to use a variable or function that hasn’t been declared yet, or it’s misspelled. The program cannot find a reference to the element you’re trying to use.

• Example:

// This will cause a ReferenceError because "message" is not declared
console.log(message);

2. SyntaxError:

This error occurs when there’s a mistake in the structure or grammar of your code. It violates the rules of the programming language you’re using.

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• Example:

// Missing semicolon after the variable declaration will cause a SyntaxError
let name = "Alice"
console.log(name)

3. TypeError:

This error occurs when you try to perform an operation on a value that isn’t the expected type. For example, trying to add a string and a number. The program encounters a type mismatch.

• Example:

// Trying to add a string and a number will cause a TypeError
let age = 25;
let name = "Bob";
console.log(age + name);  // This will result in a TypeError

Here’s a table summarizing the key differences: