freeCodeCamp/guide/english/certifications/javascript-algorithms-and-data-structures/basic-javascript/declare-javascript-variables/index.md

---
title: Declare JavaScript Variables
---
# Declare JavaScript Variables


---
## Hints

### Hint 1
When we store data in a data structure, we call it a variable. JavaScript variables are written in camel case. An example of camel case is: `camelCase`.

You can declare a variable this way

```js
var myName = "Rafael";
```

ES6 introduced two other ways to declare variables. __let__ and __const__. _Let_ is pretty similar to var and for the most part is interchangeable:

```js
let myAge = 36;
```
Where _let_ differs, is in its scope. When we declare using _var_, it's global in scope. When we declare using _let_, the scope is limited to that function. If you want to use a _let_ variable outside a function, you have to make it global in scope or redeclare it in the next function. 


__const__, on the other hand, can only be declared once. Its value can never change. 


---
## Solutions

<details><summary>Solution 1 (Click to Show/Hide)</summary>

```js
const myName = "Christina";
```
</details>