Variables in TypeScript

Variables are one of the most basic building blocks of any TypeScript program. They allow you to store information such as names, numbers, user data, and application settings. If you're familiar with JavaScript, you'll find TypeScript variables very familiar, but TypeScript gives you an extra layer of type safety.

TypeScript uses the same let, const, and var keywords as JavaScript. However, you can specify the expected data type using a colon (:).

For example:

Here, must contain a string, must contain a number, and must contain a boolean value. If you accidentally assign the wrong type, TypeScript can warn you before the application runs.

In modern TypeScript development, and are generally preferred over .

Use when the value needs to change:

Use when the value should not be reassigned: