# 3.1 Window
BOM = Browser Object Model，中文即「瀏覽器物件模型」。
在 practice 資料夾下，建立 `window.html` 來練習。
## 認識 window 物件
打開 Google 頁面(或任何網站都可)，在 console 中，輸入 window 物件。如下圖：
有龐大的函式、物件等可以使用。例如簡單常用的：
```javascript
alert("popup 訊息");
```
完整的寫法，是：
```javascript
window.alert("popup 訊息");
```
## window 視窗寬高
* window\.innerWidth
* window\.outerWidth
* window\.innerHeight
* window\.outerHeight
下圖以高度(Height)為例(寬度同理)：
編輯 `window.html`，完整內容如下，執行看看：
```markup
```
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