# grainbox/routing
The full example can be found here: https://unpkg.com/grainbox/examples/routing/routing.html
This example will cause a web page to render with the word "send" displayed on the screen, then 2 seconds later, `history.push` is used to transition to the read page, upon which the word "read" will appear on screen.
```html
```
```js
// one.js
import {html} from "https://unpkg.com/grainbox";
const element = html`one
`
export default element
```
```js
// two.js
import {html} from "https://unpkg.com/grainbox";
const element = html`two
`
export default element
```
## Full API
```
function registerRoute(
root: HTMLElement,
path: string,
callback: () => Promise<{ default: HTMLElement }>
)
```
* `root` - The page `element` will become a child of this root when the URL bar matches the path.
* `path` - See [`regexparam`](https://www.npmjs.com/package/regexparam) for more information on which kinds of path strings are supported.
* `callback` - This should be a function, which will be called when the URL matched the path, and which will return dynamic import of the element to be mounted.