TypeScript Primitives: String, Number, and Boolean Type

In this article, we are going to learn about TypeScript primitives: string, number, and boolean Type in Typescript. These are the most used and basic data types. Below we will learn about string, number, and boolean in detail.

TypeScript Primitive DataTypes

Similar to JavaScript’s mostly used data types TypeScript has mainly 3 primitives

• String: TypeScript Strings are similar to sentences. They are made up of a list of characters, which is essentially just an “array of characters, like “Hello GeeksforGeeks” etc.
• Number: Just like JavaScript, TypeScript supports number data type. All numbers are stored as floating point numbers.
• Boolean: The most basic datatype is the simple true/false value, which JavaScript and TypeScript call a boolean value.

String Type

The string data type represents text or sequences of characters. Strings are enclosed in single or double quotes in JavaScript and TypeScript.

Syntax

let variableName: string = "value";

Where

• variableName: This is the name of the variable.
• string: This is the type annotation specifying that the variable should store a string.
• “value“: This is the initial value assigned to the variable.

Example: In this example, we will learn about string

Javascript

let gfg: string = "GeeskforGeeks";
console.log(gfg)

Output:

Number Type

The number data type represents numeric values, both integers and floating-point numbers.

Syntax

let variableName: number = numericValue;

Where,

• variableName: This is the name of the variable.
• number: This is the type annotation specifying that the variable should store a numeric value (integer or floating-point).
• numericValue: This is the initial numeric value assigned to the variable.

Example: In this example, we will learn about number

Javascript

let num: number = 30;
let float: number = 19.99;
console.log(num)
console.log(float)

Output:

Boolean Type

The boolean data type represents a binary value, which can be either true or false. It is often used for conditions and logical operations.

Syntax

let variableName: boolean = true | false;

Where,

• variableName: This is the name of the variable.
• boolean: This is the type annotation specifying that the variable should store a boolean value, which can be true or false.
• true or false: These are the initial boolean values assigned to the variable

Example: In this example, we will learn about boolean

Javascript

let isStudent: boolean = true;
let hasPermission: boolean = false;
console.log(isStudent)
console.log(hasPermission)

Output:

Reference: https://www.typescriptlang.org/docs/handbook/2/everyday-types.html#the-primitives-string-number-and-boolean