JavaScript Errors

5 Types of Error In JavaScript

Jawad
2 min readMar 14, 2023

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When an error occurs, JavaScript will normally stop and generate an error message.

The technical term for this is: JavaScript will throw an exception (throw an error).

# Syntax Error:

Syntax Error is triggered when you write code that is not syntactically correct. Syntax Errors Can happen for:

  1. Missing Inverted Commas
  2. Missing Parenthesis
  3. Improper alignment of curly braces and other characters

# Type Error:

Type Error is created when some value doesn’t turn out to be of a particular expected type.

Some factors that occurs Type Errors, are:

  1. Calling Objects that are not methods
  2. Attempting to access properties of a null or undefined objects
  3. Treating a string as number or vice versa

# Reference Error:

ReferenceError object represents an error when a variable that doesn't exist (or hasn't yet been initialised) in the current scope is referenced

Some cause of Reference Errors are:

  1. Forgotten to define a value for the variable before using it
  2. We might be trying to use an inaccessible variable in our code
  3. Making a typo in a variable name
  4. Trying to access block scoped variables outside of their scopes

# Internal Error:

The Internal error occurs when an exception occurs in the JavaScript runtime engine. It may or may not indicate an issue with your code.

Internal Error occurs in two scenarios only:

  1. When a patch or JavaScript runtime carries a bug that throws exceptions
  2. When your code contains entities that are two large for the JavaScript engine (e.g. too many switch cases, too large array initializers & much recursions)

# Range Error:

Range Error: Thrown when a value is not in an allowed range

More About JavaScript Error: https://www.w3schools.com/js/js_errors.asp

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Jawad

Self-taught Software Engineering Student at OSSU | want to connect with me? Mail- abidibnazam@gmail.com