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+---
+layout: ~/layouts/Main.astro
+title: Collections
+---
+
+**Collections** are a special type of [Page](./astro-pages) that help you generate multiple pages from a larger set of data. Example use-cases include:
+
+- Pagination: `/posts/1`, `/posts/2`, etc.
+- Grouping content by author: `/author/fred`, `/author/matthew`, etc.
+- Grouping content by some tag: `/tags/red`, `/tags/blue`, etc.
+- Working with remote data
+- Mixing remote and local data
+
+**Use a Collection when you need to generate multiple pages from a single template.**  If you just want to generate a single page (ex: a long list of every post on your site) then you can just fetch that data on a normal Astro page without using the Collection API.
+
+## Using Collections
+
+To create a new Astro Collection, you must do three things:
+
+1. Create a new file in the `src/pages` directory that starts with the `$` symbol. This is required to enable the Collections API.
+
+- Example: `src/pages/$posts.astro` -> `/posts/1`, `/posts/2`, etc.
+- Example: `src/pages/$tags.astro` -> `/tags/:tag` (or `/tags/:tag/1`)
+
+2. Define and export the `collection` prop: `collection.data` is how you'll access the data for every page in the collection. Astro populates this prop for you automatically. It MUST be named `collection` and it must be exported.
+
+- Example: `const { collection } = Astro.props;`
+
+3. Define and export `createCollection` function: this tells Astro how to load and structure your collection data. Check out the examples below for documentation on how it should be implemented. It MUST be named `createCollection` and it must be exported.
+
+- Example: `export async function createCollection() { /* ... */ }`
+- API Reference: [createCollection][collection-api]
+
+## Example: Simple Pagination
+
+```jsx
+---
+// Define the `collection` prop.
+const { collection } = Astro.props;
+
+// Define a `createCollection` function.
+export async function createCollection() {
+  const allPosts = Astro.fetchContent('../posts/*.md'); // fetch local posts.
+  allPosts.sort((a, b) => a.title.localeCompare(b.title)); // sort by title.
+  return {
+    // Because you are not doing anything more than simple pagination,
+    // its fine to just return the full set of posts for the collection data.
+    async data() { return allPosts; },
+    // number of posts loaded per page (default: 25)
+    pageSize: 10,
+  };
+}
+---
+<html lang="en">
+  <head>
+    <title>Pagination Example: Page Number {collection.page.current}</title>
+  </head>
+  <body>
+    {collection.data.map((post) => (
+      <h1>{post.title}</h1>
+      <time>{formatDate(post.published_at)}</time>
+      <a href={post.url}>Read Post</a>
+    ))}
+  </body>
+</html>
+```
+
+## Example: Pagination Metadata
+
+```jsx
+---
+// In addition to `collection.data` usage illustrated above, the `collection`
+// prop also provides some important metadata for you to use, like: `collection.page`,
+// `collection.url`, `collection.start`, `collection.end`, and `collection.total`.
+// In this example, we'll use these values to do pagination in the template.
+const { collection } = Astro.props;
+export async function createCollection() { /* See Previous Example */ }
+---
+<html lang="en">
+  <head>
+    <title>Pagination Example: Page Number {collection.page.current}</title>
+    <link rel="canonical" href={collection.url.current} />
+    <link rel="prev" href={collection.url.prev} />
+    <link rel="next" href={collection.url.next} />
+  </head>
+  <body>
+    <main>
+      <h5>Results {collection.start + 1}–{collection.end + 1} of {collection.total}</h5>
+      {collection.data.map((post) => (
+        <h1>{post.title}</h1>
+        <time>{formatDate(post.published_at)}</time>
+        <a href={post.url}>Read Post</a>
+      ))}
+    </main>
+    <footer>
+      <h4>Page {collection.page.current} / {collection.page.last}</h4>
+      <nav class="nav">
+        <a class="prev" href={collection.url.prev || '#'}>Prev</a>
+        <a class="next" href={collection.url.next || '#'}>Next</a>
+      </nav>
+    </footer>
+  </body>
+</html>
+```
+
+## Example: Grouping Content by Tag, Author, etc.
+
+```jsx
+---
+// Define the `collection` prop.
+const { collection } = Astro.props;
+
+// Define a `createCollection` function.
+// In this example, we'll customize the URLs that we generate to
+// create a new page to group every pokemon by first letter of their name.
+export async function createCollection() {
+  const allPokemonResponse = await fetch(`https://pokeapi.co/api/v2/pokemon?limit=150`);
+  const allPokemonResult = await allPokemonResponse.json();
+  const allPokemon = allPokemonResult.results;
+  const allLetters = ['a','b','c','d','e','f','g','h','i','j','k','l','m','n','o','p','q','r','s','t','u','v','w','x','y','z'];
+  return {
+    // `routes` defines the total collection of routes as `params` data objects.
+    // In this example, we format each letter (ex: "a") to params (ex: {letter: "a"}).
+    routes: allLetters.map(letter => {
+      const params = {letter};
+      return params;
+    }),
+    // `permalink` defines the final URL for each route object defined in `routes`.
+    // It should always match the file location (ex: `src/pages/$pokemon.astro`).
+    permalink: ({ params }) => `/pokemon/${params.letter}`,
+    // `data` is now responsible for return the data for each page.
+    // Luckily we had already loaded all of the data at the top of the function,
+    // so we just filter the data here to group pages by first letter.
+    // If you needed to fetch more data for each page, you can do that here as well.
+    async data({ params }) {
+      return allPokemon.filter((pokemon) => pokemon.name[0] === params.letter);
+    },
+    // Finally, `pageSize` and `pagination` is still on by default. Because
+    // we don't want to paginate the already-grouped pages a second time, we'll
+    // disable pagination.
+    pageSize: Infinity,
+  };
+}
+---
+<html lang="en">
+  <head>
+    <title>Pokemon: {collection.params.letter}</head>
+  <body>
+    {collection.data.map((pokemon) => (<h1>{pokemon.name}</h1>))}
+  </body>
+</html>
+```
+
+## Example: Individual Pages from a Collection
+
+```jsx
+---
+// Define the `collection` prop.
+const { collection } = Astro.props;
+
+// Define a `createCollection` function.
+// In this example, we'll create a new page for every single pokemon.
+export async function createCollection() {
+  const allPokemonResponse = await fetch(`https://pokeapi.co/api/v2/pokemon?limit=150`);
+  const allPokemonResult = await allPokemonResponse.json();
+  const allPokemon = allPokemonResult.results;
+  return {
+    // `routes` defines the total collection of routes as data objects.
+    routes: allPokemon.map((pokemon, i) => {
+      const params = {name: pokemon.name, index: i};
+      return params;
+    }),
+    // `permalink` defines the final URL for each route object defined in `routes`.
+    permalink: ({ params }) => `/pokemon/${params.name}`,
+    // `data` is now responsible for return the data for each page.
+    // Luckily we had already loaded all of the data at the top of the function,
+    // so we just filter the data here to group pages by first letter.
+    // If you needed to fetch more data for each page, you can do that here as well.
+    // Note: data() is expected to return an array!
+    async data({ params }) {
+      return [allPokemon[params.index]];
+    },
+    // Note: The default pageSize is fine because technically only one data object
+    // is ever returned per route. We set it to Infinity in this example for completeness.
+    pageSize: Infinity,
+  };
+}
+---
+<html lang="en">
+  <head>
+    <title>Pokemon: {collection.params.name}</head>
+  <body>
+    Who's that pokemon? It's {collection.data[0].name}!
+  </body>
+</html>
+```
+
+## Tips
+
+- If you find yourself duplicating markup across many pages and collections, you should probably be using more reusable components.
+
+### 📚 Further Reading
+
+- [Fetching data in Astro][docs-data]
+- API Reference: [collection][collection-api]
+- API Reference: [createCollection()][create-collection-api]
+- API Reference: [Creating an RSS feed][create-collection-api]
+
+[docs-data]: ../README.md#-fetching-data
+[collection-api]: ./api.md#collection
+[create-collection-api]: ./api.md#createcollection
+[example-blog]: ../examples/blog
+[fetch-content]: ./api.md#fetchcontent