> For the complete documentation index, see [llms.txt](https://simplereact.gitbook.io/simplereact/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://simplereact.gitbook.io/simplereact/master.md).

# 01. React 시작해보기

### 리액트란 ?

페이스북에서 개발하고 관리되어오고 있는 UI 전용 라이브러리입니다.

* 가상 돔을 이용한다 
* 돔에 대한 업데이트 처리를 신경쓰지 않아도된다.
* 컴포넌트 단위로 이루어져 개발, 유지보수에 좋다 등등... 

### 들어가기전

모던한 프론트엔드 라이브러리와 프레임워크들에서는 Componet 와 SPA 개념이 중요합니다.\
Component 와 SPA 에 관한 설명은 [여기](https://simplevue.gitbook.io/intro/vue.js#component)를 참고해주세요  

#### Create-React-App (CRA) 

CRA 는 별다른 설정없이 간단하게 React 프로젝트를 구성할 수 있도록 도와줍니다.\
CRA 를 이용하여 리액트 프로젝트를 생성해보겠습니다. 

```bash
$ npx create-react-app my-app
$ cd my-app
$ npm start
```

![](/files/-LngVwAdQhHSIAdE_7vl)


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