# Box Model

In addition to setting an element's `height` and `width`, elements have three other properties that explicitly control spacing:

1. 'Padding' specifies spacing between the inside of an element's border and the contents of that element (which includes `height` and `width`!)
2. 'Border' sets a perimeter around an element. In addition to specifying a color and a particular type of border, you can also specify a thickness.
3. 'Margin' specifies spacing between the outside of an element's border and any adjacent elements.

Together, these attributes form *the box model*, a way of describing the space taken up by an element.

![Box Model](https://i.imgur.com/D1WrM6t.png)

By default, the *total size* of an element can be calculated with:

```
`width` = `width` + horizontal `padding` + horizontal `border`
and
`height` = `height` + vertical `padding` + vertical `border`
```

A newer, and arguably better way, is to set the element's CSS [`box-sizing`](https://developer.mozilla.org/en-US/docs/Web/CSS/box-sizing) property to `border-box` instead of the default `content-box`.


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