Why am I getting an error `ReferenceError: ____ is not defined`?

Frequently Asked Questions JavaScript FAQ
1

Question

Why am I getting an error ReferenceError: ____ is not defined?

Answer

Make sure to include the quotation marks in your bracket notation! Proper syntax for bracket notation requires you to use quotation marks ” or single quotes ’ around the key name inside of the brackets in order to access the key’s value. For example:

// If we have the following object:

				let dog = {
							name: ‘Max’,
	breed: ‘Chihuahua’
				};

		// These both work:
					console.log(dog[‘breed’]);
console.log(dog[“breed”]);

// This doesn’t:
				
console.log(dog[breed]);