Describe compiled CSS (#24271)

README.md

@@ -71,7 +71,15 @@ bootstrap/
 │   ├── bootstrap.css
 │   ├── bootstrap.css.map
 │   ├── bootstrap.min.css
-│   └── bootstrap.min.css.map
+│   ├── bootstrap.min.css.map
+│   ├── bootstrap-grid.css
+│   ├── bootstrap-grid.css.map
+│   ├── bootstrap-grid.min.css
+│   ├── bootstrap-grid.min.css.map
+│   ├── bootstrap-reboot.css
+│   ├── bootstrap-reboot.css.map
+│   ├── bootstrap-reboot.min.css
+│   └── bootstrap-reboot.min.css.map
 └── js/
     ├── bootstrap.js
     └── bootstrap.min.js

docs/4.0/getting-started/contents.md

@@ -18,7 +18,15 @@ bootstrap/
 │   ├── bootstrap.css
 │   ├── bootstrap.css.map
 │   ├── bootstrap.min.css
-│   └── bootstrap.min.css.map
+│   ├── bootstrap.min.css.map
+│   ├── bootstrap-grid.css
+│   ├── bootstrap-grid.css.map
+│   ├── bootstrap-grid.min.css
+│   ├── bootstrap-grid.min.css.map
+│   ├── bootstrap-reboot.css
+│   ├── bootstrap-reboot.css.map
+│   ├── bootstrap-reboot.min.css
+│   └── bootstrap-reboot.min.css.map
 └── js/
     ├── bootstrap.js
     └── bootstrap.min.js
@@ -26,6 +34,52 @@ bootstrap/
 
 This is the most basic form of Bootstrap: precompiled files for quick drop-in usage in nearly any web project. We provide compiled CSS and JS (`bootstrap.*`), as well as compiled and minified CSS and JS (`bootstrap.min.*`). CSS [source maps](https://developers.google.com/web/tools/chrome-devtools/javascript/source-maps) (`bootstrap.*.map`) are available for use with certain browsers' developer tools.
 
+### Comparison of CSS files
+
+<table class="table table-bordered table-responsive">
+  <thead>
+    <tr>
+      <th scope="col">CSS files</th>
+      <th scope="col" class="text-center">Layout</th>
+      <th scope="col" class="text-center">Content</th>
+      <th scope="col" class="text-center">Components</th>
+      <th scope="col" class="text-center">Utilities</th>
+    </tr>
+  </thead>
+  <tbody>
+    <tr>
+      <th scope="row">
+        <div><code class="text-nowrap">bootstrap.css</code></div>
+        <div><code class="text-nowrap">bootstrap.min.css</code></div>
+      </th>
+      <td class="table-success text-center align-middle">All</td>
+      <td class="table-success text-center align-middle">All</td>
+      <td class="table-success text-center align-middle">All</td>
+      <td class="table-success text-center align-middle">All</td>
+    </tr>
+    <tr>
+      <th scope="row">
+        <div><code class="text-nowrap">bootstrap-grid.css</code></div>
+        <div><code class="text-nowrap">bootstrap-grid.min.css</code></div>
+      </th>
+      <td class="table-warning text-center align-middle">Only <a href="{{ site.baseurl }}/docs/{{ site.docs_version }}/layout/grid/">grid</a> system</td>
+      <td class="table-danger text-center align-middle">No</td>
+      <td class="table-danger text-center align-middle">No</td>
+      <td class="table-warning text-center align-middle">Only <a href="{{ site.baseurl }}/docs/{{ site.docs_version }}/utilities/flex/">flex</a> utilities</td>
+    </tr>
+    <tr>
+      <th scope="row">
+        <div><code class="text-nowrap">bootstrap-reboot.css</code></div>
+        <div><code class="text-nowrap">bootstrap-reboot.min.css</code></div>
+      </th>
+      <td class="table-danger text-center align-middle">No</td>
+      <td class="table-warning text-center align-middle">Only <a href="{{ site.baseurl }}/docs/{{ site.docs_version }}/content/reboot/">Reboot</a></td>
+      <td class="table-danger text-center align-middle">No</td>
+      <td class="table-danger text-center align-middle">No</td>
+    </tr>
+  </tbody>
+</table>
+
 ## Bootstrap source code
 
 The Bootstrap source code download includes the precompiled CSS and JavaScript assets, along with source Sass, JavaScript, and documentation. More specifically, it includes the following and more:

docs/4.0/getting-started/download.md

@@ -10,7 +10,7 @@ toc: true
 
 Download ready-to-use compiled code for **Bootstrap v{{ site.current_version}}** to easily drop into your project, which includes:
 
-- Compiled and minified CSS bundles (default, grid-only, and Reboot-only)
+- Compiled and minified CSS bundles (see [CSS files comparison]({{ site.baseurl }}/docs/{{ site.docs_version }}/getting-started/contents/#comparison-of-css-files))
 - Compiled and minified JavaScript plugins
 
 This doesn't include documentation, source files, or any optional JavaScript dependencies (jQuery and Popper.js).