# Rail
Rails display optional accompanying content outside of the main viewport of your website. Sites often use rails with sticky content to fix additional—often optional—content to your viewport as you scroll through the page.
```example
Right rail content
```
## Variations
### Internal
```example
Right rail content
```
### Dividing
```example
Right rail content
```
### Attached
```example
Right rail content
```
```example
Right rail content
```
### Close
```example
Right rail content
```
```example
Right rail content
```
### Sizes
```example
Right rail content
```