Search Engine Optimization

When it comes to finding things on the web, almost everyone does so using a search engine. There's a growing diversity of search engines, but still Google is the king πŸ‘‘. Helping search engines like Google to properly categorize your content is called Search Engine Optimization (SEO). It's a very broad topic, and we're not going to cover the specifics of everything here. Our primary goal is to help you understand how to properly use metadata tags (like meta and title) to help search engines categorize your content.
Lots of what applies to search engines also applies to other tools and social media platforms as well. So it's a good idea to spend some time thinking about your website's sources of traffic and learning how to optimize your website's presentation on those platforms.

The web

The <title> tag appears in the <head> and is typically what is displayed in the browser tab. It's also what is displayed in search engine results.
<html>
	<head>
		<title>My Page</title>
	</head>
	<body>
		<!-- ... -->
	</body>
</html>
The <meta> tag is used to provide metadata about the page. It's typically used to provide information about the page to search engines. The name attribute is used to specify the type of metadata, and the content attribute is used to provide the actual metadata.
The description metadata is used to provide a short description of the page and is often used in search engine results as well as social media preview cards.
<html>
	<head>
		<title>My Page</title>
		<meta name="description" content="This is my page" />
	</head>
	<body>
		<!-- ... -->
	</body>
</html>
Meta tags aren't only for search engines. They can also be used to provide configuration information to other tools. For example, the viewport metadata is used to configure the viewport of a mobile browser.
<html>
	<head>
		<title>My Page</title>
		<meta name="description" content="This is my page" />
		<meta name="viewport" content="width=device-width, initial-scale=1" />
	</head>
	<body>
		<!-- ... -->
	</body>
</html>
What this does is tell the browser to set the width of the viewport to the width of the device, and to set the initial zoom level to 1. This is a common configuration for mobile browsers.
A final example is the charset metadata. This is used to specify the character encoding of the page.
<html>
	<head>
		<title>My Page</title>
		<meta name="description" content="This is my page" />
		<meta name="viewport" content="width=device-width, initial-scale=1" />
		<meta charset="utf-8" />
	</head>
	<body>
		<!-- ... -->
	</body>
</html>
This is pretty much always how you'd want to configure charset, unless you're doing something funky with character encodings.
There are many other types of metadata that can be provided, but we'll leave that as an exercise for the reader (you can learn more about meta tags on seosherpa.com).

In Remix

Because you're responsible for everything between the <html> and </html> in your document, adding metadata tags is as simple as adding them to your JSX.
export default function App() {
	return (
		<html>
			<head>
				<title>My Page</title>
				<meta name="description" content="This is my page" />
				<meta name="viewport" content="width=device-width, initial-scale=1" />
				<meta charSet="utf-8" />
			</head>
			<body>{/* ... */}</body>
		</html>
	)
}
However, things can get tricky when we start thinking about nested routes and having that title and description be dynamic based on the current route. That's why Remix has a built-in API for routes defining the meta tags that should be used when the route is active through the route meta export. It's similar in some ways to the links export, but instead, when a route defines a meta export, the meta tags from ancestor routes are ignored and must be manually merged. This avoids conflicts between routes that might have the same meta tags. However, you do have access to the parent metas in the meta function so you can merge them yourself if you so desire.
import { type MetaFunction } from '@remix-run/react'

export const meta: MetaFunction = () => {
	return [
		{ title: 'Sandwich Shop' },
		{ name: 'description', content: 'Fill your tummy with something yummy' },
	]
}
Again, in Remix you're responsible for everything on the page between <html> and </html> and that's no different here. You need to apply the <Meta /> component in the <head> of your document in your app/root.tsx to ensure these meta tags are rendered. Much like the <Links /> component.
With that example above, the <head> of your document would have this:
<title>Sandwich Shop</title>
<meta charset="utf-8" />
<meta name="viewport" content="width=device-width,initial-scale=1" />
<meta name="description" content="Fill your tummy with something yummy" />
You can also access dynamic data (data from your loader) in the meta export so you can dynamically set the title, description, og:image, etc for your page.
import { json } from '@remix-run/node'
import { type MetaFunction } from '@remix-run/react'
import { getSandwich } from '../sandwiches.server'

export const meta: MetaFunction<typeof loader> = ({ data }) => {
	return [
		{ title: data.sandwich.name },
		{ name: 'description', content: data.sandwich.description },
	]
}

export function loader({ params }) {
	return json({ sandwich: getSandwich(params.sandwichId) })
}