Merge commit '9b0050e9aabe4be65c78ccf292a348f309d50ccd' as 'docs'

```
git subtree add --prefix=docs/ https://github.com/gohugoio/hugoDocs.git master --squash
```

Closes #11925

docs/content/en/quick-reference/_index.md

@@ -0,0 +1,16 @@
+---
+title: Quick reference guides
+linkTitle: Overview
+description: Quick reference guides to Hugo's features, functions, and methods.
+categories: []
+keywords: []
+menu:
+  docs:
+    identifier: quick-reference-overview
+    parent: quick-reference
+    weight: 10
+weight: 10
+showSectionMenu: false
+---
+
+Quick reference guides to Hugo's features, functions, and methods.

docs/content/en/quick-reference/functions.md

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+---
+title: Functions
+description: A quick reference guide to Hugo's functions, grouped by namespace. Aliases, if any, appear in parentheses to the right of the function name.
+categories: [quick reference]
+keywords: []
+menu:
+  docs:
+    parent: quick-reference
+    weight: 30
+weight: 30
+toc: true
+---
+
+{{% quick-reference section="functions" %}}

docs/content/en/quick-reference/methods.md

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+---
+title: Methods
+description: A quick reference guide to Hugo's methods, grouped by object.
+categories: [quick reference]
+keywords: []
+menu:
+  docs:
+    parent: quick-reference
+    weight: 40
+weight: 40
+toc: true
+---
+
+{{% quick-reference section="methods" %}}

docs/content/en/quick-reference/page-collections.md

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+---
+title: Page collections
+description: A quick reference guide to Hugo's page collections.
+categories: [quick reference]
+keywords: []
+menu:
+  docs:
+    parent: quick-reference
+    weight: 50
+weight: 50
+toc: true
+---
+
+## Page
+
+Use these `Page` methods when rendering lists on [section] pages, [taxonomy] pages, [term] pages, and the home page.
+
+[section]: /getting-started/glossary/#section
+[taxonomy]: /getting-started/glossary/#taxonomy
+[term]: /getting-started/glossary/#term
+
+{{< list-pages-in-section path=/methods/page filter=methods_page_page_collections filterType=include omitElementIDs=true titlePrefix=PAGE. >}}
+
+## Site
+
+Use these `Site` methods when rendering lists on any page.
+
+{{< list-pages-in-section path=/methods/site filter=methods_site_page_collections filterType=include omitElementIDs=true titlePrefix=SITE. >}}
+
+## Filter
+
+Use the [`where`] function to filter page collections.
+
+[`where`]: /functions/collections/where
+
+## Sort
+
+Use these methods to sort page collections.
+
+{{< list-pages-in-section path=/methods/pages filter=methods_pages_sort filterType=include titlePrefix=. omitElementIDs=true titlePrefix=PAGES. >}}
+
+## Group
+
+Use these methods to group page collections.
+
+{{< list-pages-in-section path=/methods/pages filter=methods_pages_group filterType=include titlePrefix=. omitElementIDs=true titlePrefix=PAGES. >}}