freeCodeCamp/guide/english/react-native/hello-world/index.md

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2018-10-12 19:37:13 +00:00
---
title: Hello World
---
## Hello World
In a traditional webpage, you could easily render `Hello World!` to the screen by writing some HTML like this:
```html
<!DOCTYPE html>
<html>
<head>
<title>Test Page</title>
</head>
<body>
<p>Hello World!</p>
</body>
</html>
```
In React Native, there is no DOM or browser, so you have to render things to the screen from a mobile API that React Native provides. For example, instead of using a `<p>` tag as a wrapper for text like you would on the web, you would use `<Text>`; instead of `<div>` container tags, you would use `<View>`.
```js
import React, { Component } from react;
import { AppRegistry, View, Text } from react-native;
class App extends Component {
render () {
return (
<View>
<Text> Hello World! </Text>
</View>
);
}
}
AppRegistry.registerComponent(AwesomeProject, () => App);
```
To render the code to the screen, instead of opening the page in a browser, you use a special `AppRegistry.registerComponent()` method provided by React Native to render the app to a mobile device.