Data Types

Question 1

What are data types?

Answer 1

A value in JavaScript is always of a certain type. For example, a string or a number.

Question 2

What are the 7 primitive data types?

Answer 2

Number.
String.
Boolean.
Undefined.
Null.
Symbol.
BigInt.

Question 3

What is a non-primitive data type?

Answer 3

Object.
(an array is not a special data type in JavaScript, it belongs to the object data types)

Question 4

What is a Number data type?

Answer 4

The number type represents both integer and floating point numbers.

Question 5

What is a String data type?

Answer 5

A string (or a text string) is a series of characters like “John Doe”.

Question 6

What is a Boolean data type?

Answer 6

The boolean type has only two values: true and false.

Question 7

What is an Undefined data type?

Answer 7

In JavaScript, a variable without a value, has the value undefined. The type is also undefined.

Question 8

What is a Null data type?

Answer 8

It’s a special value which represents “nothing”, “empty” or “value unknown”.

Question 9

What is a Symbol data type?

Answer 9

Symbols are unique identifiers used within objects.

Question 10

What is a BigInt data type?

Answer 10

BigInt is a datatype that can be used to store integer values that are too big to be represented by a normal JavaScript Number.

Question 11

What is an Array?

Answer 11

An array is a special variable, which can hold more than one value:

Question 12

What is an Object?

Answer 12

Objects are used to store keyed collections of various data.