> For the complete documentation index, see [llms.txt](https://hochan049.gitbook.io/cs-interview/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://hochan049.gitbook.io/cs-interview/javascript/undefined.md).

# 질문 목록

#### 1. 호이스팅이란?

#### 2. var, let, const의 차이 설명

#### 3. JS Drag Drop 구현 방법은?

#### 4. 웹 브라우져에서 사이트를 렌더링 하는 과정

#### 5. 웹 최적화 기법에는 무엇이 있나?

#### 6. 이터러블과 이터레이터 프로콜에 대해 설명해 주세요.

#### 7. DOM 이벤트 전파에는 어떤 방식이 있는지? event method를 호출하면 어떤 일이 일어나는지?

#### 8. script tag의 async, defer 키워드가 무엇인지?

#### 9. 정규표현식이란?

#### 10. javascript ES5, ES6 차이는?

#### 11. encoding이 뭔지, javascript의 한글은 몇바이트인지, string에 문자열은 어떻게 저장되나?

#### 12. mutable, immutable

#### 13. 크로스플랫폼이란?

#### 14. 비동기 서버에 대해 설명해주세요.

#### 15. 가비지 컬렉션에 대해 설명해주세요.

#### 16. garbage collector가 언제 작동하는지, 정리 대상 클래스를 어떻게 판별하는지

#### 17. parseInt()와 Number() 차

성능은 Number()가 parseInt()보다 약 2배 좋다.

```javascript
parseInt("1000ab"); // 1000
Number("1000ab"); // NaN
```

#### 18. toString()과 String() 차이

String()이 toString()보다 약 2배 빠르다.

#### 19. object vs map

자료를 get 할 일이 많으면 Map, set할 일이 더 많으면 객체가 유리하다.

{% embed url="<https://medium.com/@wdjty326/javascript-es6-map-vs-object-performance-%EB%B9%84%EA%B5%90-7f98e30bf6c8>" %}

#### 20. promise

{% embed url="<https://levelup.gitconnected.com/javascript-interview-questions-promises-400c51805cbe>" %}

#### 21. scope

{% embed url="<https://graceywilliams594.medium.com/scopes-in-javascript-fe69f368643e>" %}


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