1.js-basics.md

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JavaScript

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JavaScript Basics JavaScript Functions JavaScript Arrays JavaScript Objects JavaScript and the DOM HTTP and Fetch

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# JavaScript Basics

JavaScript brings your pages to life. It runs in the browser and can change anything on the page after it loads.

## Variables with let and const

Variables store values. Use `const` for values that never change and `let` for ones that do.

```js
const title = "hackweb.dev";
let score = 0;
score = score + 10;
console.log(title, score);
```

## Values and types

JavaScript has a few core types — numbers, strings, booleans, and more.

```js
const age = 25;          // number
const name = "Ada";      // string
const isAdmin = true;    // boolean
console.log(typeof age, typeof name, typeof isAdmin);
```

## Strings

Strings are text. Join them with `+` or with template literals.

```js
const first = "Ada";
const last = "Lovelace";
const full = `${first} ${last}`;
console.log(full);
```

## console.log

`console.log` prints values to the console — your best debugging friend.

```js
console.log("hello from the console");
```

## The event loop

JavaScript handles one thing at a time, but things like timers happen in the background. The **event loop** is how they come back. Watch it in action:

```animation
name="event-loop"
```

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