Add storybook intro

storybook/stories/docs/introduction.story.mdx

@@ -4,4 +4,37 @@ import { Meta } from '@storybook/addon-docs';
 
 # Introduction
 
-Hello World
+## Welcome!
+
+The WordPress Gutenberg project uses Storybook to view and work with the UI components developed in the WordPress package [@wordpress/components](https://github.com/WordPress/gutenberg/tree/trunk/packages/components).
+
+On this interactive site you can browse individual components, their controls, options, and settings in isolation. You can also modify controls and arguments and see the changes right away.
+
+The components displayed on this site can be used in your code to build the editor's UI for your custom blocks or other pages.
+Import them from the components root directory like in below example:
+
+```jsx
+import { Button } from '@wordpress/components';
+
+export default function MyButton() {
+    return <Button>Click Me!</Button>;
+}
+````
+
+## How this site works
+
+The site shows the individual components in the sidebar and the Canvas on the right. Select the component you’d like to explore, and you’ll see the display on the Canvas tab. If the component also has controls/arguments, you can modify them on the Controls tab on the lower half of the screen.
+
+To view the documentation for each component use the **Docs** menu item in the top toolbar.
+
+To use it in your local development environment run the following command in the top level Gutenberg directory:
+
+ ```bash
+ npm run storybook:dev
+ ```
+
+## Resources to learn more:
+
+- [Storybook.js.org](https://storybook.js.org/) - Storybook is a frontend workshop for building UI components and pages in isolation.
+- [[Package] Components](https://github.com/WordPress/gutenberg/issues?q=is%3Aopen+is%3Aissue+label%3A%22%5BPackage%5D+Components%22) - Open Issue Gutenberg Repo
+- [On the known "loading source..." issue](https://github.com/WordPress/gutenberg/issues/45095) at the 'Story' tab for some components