In addition to [custom components inside the `<Markdown>` component](#markdown-component), Astro comes with [GitHub-flavored Markdown](https://github.github.com/gfm/) support, [Footnotes](https://github.com/remarkjs/remark-footnotes) syntax, [Smartypants](https://github.com/silvenon/remark-smartypants), and syntax highlighting via [Prism](https://prismjs.com/) pre-enabled.
> **Note** Enabling custom `remarkPlugins` or `rehypePlugins` removes Astro's built-in support for [GitHub-flavored Markdown](https://github.github.com/gfm/) support, [Footnotes](https://github.com/remarkjs/remark-footnotes) syntax, [Smartypants](https://github.com/silvenon/remark-smartypants). You must explicitly add these plugins to your `astro.config.mjs` file, if desired.
## Add a markdown plugin in Astro
If you want to add a plugin, you need to install the npm package dependency in your project and then update the `markdownOptions.remarkPlugins` or `markdownOptions.rehypePlugins` depends on what plugin you want to have:
```js
// astro.config.js
export default {
markdownOptions: {
remarkPlugins: [
// Add a Remark plugin that you want to enable for your project.
// If you need to provide options for the plugin, you can use an array and put the options as the second item.
Astro treats any `.md` files inside of the `/src/pages` directory as pages. These pages are processed as plain markdown files and do not support components. If you're looking to embed rich components in your markdown, take a look at the [Markdown Component](#astros-markdown-component) section.
Layout files are normal `.astro` components. Any Frontmatter defined in your `.md` page will be exposed to the Layout component as the `content` prop. `content` also has an `astro` key which holds special metadata about your file, like the complete Markdown `source` and a `headings` object.
Keep in mind that the only guaranteed variables coming from the `content` prop object are `astro` and `url`. An example of what a blog post `content` object might look like is as follows:
Astro has a dedicated component used to let you render your markdown as HTML components. This is a special component that is only exposed to `.astro` files. To use the `<Markdown>` component, within yout frontmatter block use the following import statement:
```jsx
---
import { Markdown } from 'astro/components';
---
```
You can utilize this within your `.astro` file by doing the following:
If you have Markdown in a remote source, you may pass it directly to the Markdown component through the `content` attribute. For example, the example below fetches the README from Snowpack's Github repository and renders it as HTML.
There might be times when you want to combine both dynamic, and static markdown. If that is the case, you can nest `<Markdown>` components with each other to get the best of both worlds.
Yes! Just like with regular HTML, improper use of the `Markdown` component can open you up to a [cross-site scripting (XSS)](https://en.wikipedia.org/wiki/Cross-site_scripting) attack. If you are rendering untrusted content, be sure to _sanitize your content **before** rendering it_.
Rendering a string of HTML (or Markdown) is an extremely common use case when rendering a static site and you probably don't need the extra hoops to jump through. Rendering untrusted content is always dangerous! Be sure to _sanitize your content **before** rendering it_.
