---
id: html-web-apis
title: "HTML Web APIs"
category: "Frontend"
status: "draft"
verification_status: "conceptual"
canonical_id: ""
aliases: ["Web API", "Application Programming Interface", "HTML5 APIs", "browser APIs", "third party APIs"]
duplicate_of: ""
source_trust_level: "B"
confidence_score: 0.88
created_at: 2026-06-23
updated_at: 2026-06-23
review_reason: ""
merge_history: []
tags: ["html", "web", "frontend", "w3schools", "api", "html5"]
raw_sources: ["https://www.w3schools.com/html/html5_api_whatis.asp"]
applied_in: []
github_commit: ""
---

# [[HTML Web APIs]]

## 🎯 한 줄 통찰 (One-line insight)
A Web API is an application programming interface for the Web that extends browser functionality and provides easy syntax to otherwise complex code; modern browsers ship several built-in Web APIs. [S1]

## 🧠 핵심 개념 (Core concepts)
- **API = Application Programming Interface** — an interface that includes a set of functions and subroutines allowing programmers to access specific features or data of an application, operating system, or other service. [S1]
- **Web API** — an application programming interface for the Web. It can extend the functionality of the browser, greatly simplify complex functions, and provide easy syntax to complex code. [S1]
- **Built into the browser** — all browsers include a set of built-in Web APIs. [S1]
- **Third party APIs** — APIs that are not built into the browser; to use them you download the code from the Web. [S1]

## 🧩 추출된 패턴 (Extracted patterns)
- **Browser-native vs third-party** — distinguish built-in APIs (Geolocation, Drag and Drop, Web Storage, Web Workers, Server-Sent Events, Canvas) from third-party APIs you must import (YouTube, Twitter, Facebook). [S1]
- **API as an abstraction layer** — the API hides complex underlying code behind a simpler, accessible syntax. [S1]

## 📖 세부 내용 (Details)
**What is a Web API?**
API stands for **A**pplication **P**rogramming **I**nterface. An API is some kind of interface that includes a set of functions and subroutines that allow programmers to access specific features or data of an application, operating system, or other services. A Web API is an application programming interface for the Web. [S1]

**What Web APIs can do**
A Web API: [S1]
- Can extend the functionality of the browser
- Can greatly simplify complex functions
- Can provide easy syntax to complex code

**Browser APIs**
All browsers include a set of built-in Web APIs. The Web APIs covered in this tutorial are: [S1]

| API | Purpose |
|---|---|
| Geolocation API | Used to access the current location of a user (with latitude and longitude) |
| Drag and Drop API | Enables you to use drag-and-drop features in browsers |
| Web Storage API | Mechanisms to let browsers store key/value pairs (in a more intuitive way than cookies) |
| Web Workers API | Allows a JavaScript to run in the background, without affecting the performance of the page |
| Server-Sent Events API | Allows a web page to automatically get updates from a server |
| Canvas API | Lets you draw graphics, on the fly, via JavaScript |

**Third party APIs**
Third party APIs are not built into your browser. To use these APIs, you will have to download the code from the Web. Examples include: [S1]
- YouTube API
- Twitter API
- Facebook API

## 🛠️ 적용 사례 (Applied in summary)
This page is an index/overview; its "applied" value is orientation — it points to the concrete API topics (Geolocation, Drag and Drop, Web Storage, Web Workers, SSE, Canvas) that each carry their own examples. No external project/commit applications found in the source.

## 💻 코드 패턴 (Code patterns)
Not found in source — this overview page presents no code examples; concrete usage lives in the individual API topic pages (e.g. [[HTML Geolocation]], [[HTML Web Storage]]).

## ⚖️ 비교 및 선택 기준 (Comparison & decision criteria)
The page distinguishes two categories of Web APIs, which guides where the implementing code comes from: [S1]

| Category | Built into browser? | How to use |
|---|---|---|
| Browser (built-in) APIs | Yes | Available natively (Geolocation, Drag and Drop, Web Storage, Web Workers, SSE, Canvas) |
| Third party APIs | No | Download the code from the Web (e.g. YouTube, Twitter, Facebook) |

## ⚖️ 모순 및 업데이트 (Contradictions & updates)
No contradictions found in the source.

## ✅ 검증 상태 및 신뢰도
- **상태:** draft
- **검증 단계:** conceptual (실제 적용 사례 발견 시 applied/validated로 승격 가능)
- **출처 신뢰도:** B (W3Schools — widely used educational reference, not a primary standards body)
- **신뢰 점수:** 0.88
- **중복 검사 결과:** 신규 생성 (New discovery)

## 🔗 지식 그래프 (Knowledge Graph)
- **상위/루트:** [[HTML Tutorial]]
- **관련 개념:** [[HTML Geolocation]], [[HTML Drag and Drop]], [[HTML Web Storage]], [[HTML Web Workers]], [[HTML SSE]]
- **참조 맥락:** The entry point that frames the entire HTML5 Web APIs section.

## 📚 출처 (Sources)
- [S1] W3Schools — HTML Web APIs — https://www.w3schools.com/html/html5_api_whatis.asp

## 📝 변경 이력 (Change history)
- 2026-06-23: Initial draft synthesized from the W3Schools "HTML Web APIs" page (Astra wiki-curation, P-Reinforce v3.1 format).