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+---
+title: Images in Next.js
+date: '2020-11-11'
+tags: ['next js', 'guide']
+draft: false
+summary: 'In this article we introduce adding images in the tailwind starter blog and the benefits and limitations of the next/image component.'
+authors: ['sparrowhawk']
+---
+
+# Introduction
+
+The tailwind starter blog has out of the box support for [Next.js's built-in image component](https://nextjs.org/docs/api-reference/next/image) and automatically swaps out default image tags in markdown or mdx documents to use the Image component provided.
+
+# Usage
+
+To use in a new page route / javascript file, simply import the image component and call it e.g.
+
+```js
+import Image from 'next/image'
+
+function Home() {
+  return (
+    <>
+      <h1>My Homepage</h1>
+      <Image src="/me.png" alt="Picture of the author" width={500} height={500} />
+      <p>Welcome to my homepage!</p>
+    </>
+  )
+}
+
+export default Home
+```
+
+For a markdown file, the default image tag can be used and the default `img` tag gets replaced by the `Image` component in the build process.
+
+Assuming we have a file called `ocean.jpg` in `data/img/ocean.jpg`, the following line of code would generate the optimized image.
+
+```
+![ocean](/static/images/ocean.jpg)
+```
+
+Alternatively, since we are using mdx, we can just use the image component directly! Note, that you would have to provide a fixed width and height. The `img` tag method parses the dimension automatically.
+
+```js
+<Image alt="ocean" src="/static/images/ocean.jpg" width={256} height={128} />
+```
+
+_Note_: If you try to save the image, it is in webp format, if your browser supports it!
+
+![ocean](/static/images/ocean.jpeg)
+
+<p>
+  Photo by [YUCAR
+  FotoGrafik](https://unsplash.com/@yucar?utm_source=unsplash&amp;utm_medium=referral&amp;utm_content=creditCopyText)
+  on
+  [Unsplash](https://unsplash.com/s/photos/sea?utm_source=unsplash&amp;utm_medium=referral&amp;utm_content=creditCopyText)
+</p>
+
+# Benefits
+
+- Smaller image size with Webp (~30% smaller than jpeg)
+- Responsive images - the correct image size is served based on the user's viewport
+- Lazy loading - images load as they are scrolled to the viewport
+- Avoids [Cumulative Layout Shift](https://web.dev/cls/)
+- Optimization on demand instead of build-time - no increase in build time!
+
+# Limitations
+
+- Due to the reliance on `next/image`, unless you are using an external image CDN like Cloudinary or Imgix, it is practically required to use Vercel for hosting. This is because the component acts like a serverless function that calls a highly optimized image CDN.
+
+  If you do not want to be tied to Vercel, you can remove `imgToJsx` in `remarkPlugins` in `lib/mdx.js`. This would avoid substituting the default `img` tag.
+
+  Alternatively, one could wait for image optimization at build time to be supported. A different library, [next-optimized-images](https://github.com/cyrilwanner/next-optimized-images) does that, although it requires transforming the images through webpack which is not done here.
+
+- Images from external links are not passed through `next/image`
+- All images have to be stored in the `public` folder e.g `/static/images/ocean.jpeg`