# [What is the difference between webpage, website, web server, and search engine?](https://developer.mozilla.org/en-US/docs/Learn/Common_questions/Pages_sites_servers_and_search_engines)

###### tags: `what is?` `web`

> **Be able to describe the differences between a web page, a website, a web server, and a search engine.**

term 項目、用語
jargon 術語
[glossary](https://developer.mozilla.org/en-US/docs/Glossary) 詞彙表
at the outset 首先、一開始
misused 濫用、誤用
analogy 比喻
generally 通常

## web page 網頁
> **A document** which can be displayed by a browser.

:::warning
Browsers can also display other documents such as PDF files or images, but the term **web page** specifically refers to **HTML documents**.
:::

All web pages available on the web are reachable through a unique address. To access a page, just type its address in your browser address bar:


## website (site) 網站 (很多網頁的組合)
> Website always share a unique **domain name**.
A collection of web pages which are grouped together and usually connected together in various ways.

To access a website, type its domain name in your browser address bar, and the browser will display the website's main web page, or homepage: https://google.com

## [web server](https://developer.mozilla.org/en-US/docs/Learn/What_is_a_web_server) 網路服務器/伺服器
> **A computer that hosts one or more websites.**

All the web pages and files are available on that computer. That means computer can save everything. And the web server will send web page to any user's browser if they request.

Technically, we could host all files on our own computer, but it's far more convenient to store them all on a dedicated (專用) web server, because it..
* is always up and unning
* is always connected to the Internet
* has the same IP address all the time (?????????)
* is maintained by a third-party provider

:::info
The term **web server** is never used to designate a website, because web server can host multiple websites.
:::

## search engine 搜尋引擎
> **A website that helps people find other web pages from other websites**, such as Google, Bing, Yahoo.

Search engines are normally accessed (訪問) web pages through a web browser.
You can searches directly in the address bar by Firefox, Chrome...

> **A browser** is a piece of software that retrieves (檢索) and displays web pages.
The confusion arises because people launches a browser, the browser displays a cearch engine's homepage. That make sense, obviously, the first thing you want to do with a browser is to find a web page to display.

**Compare the library with a web server:**

:::info
* The **library** is like a **web server**.
* Library has **several books**, which is similar to a web server hosting **multiple websites**.
* The **books** are like **websites**. One website may have several webpages, the History section (the website) will have books on Europe, Asia, 19th (the webpages). Webpages can each be found at a unique location (URL).
* The **search index** is like the **search engine**. Each book has its own unique location in the library.
:::

| Library 圖書館| Web Server 服務器 |
| -------- | -------- |
| books 書籍 (目錄) | websites 網站 (首頁) |
| pages 書頁 | webpages 網頁 |
| index 索引 | search engine 搜尋引擎 |