Adds content to the source README.md file

LICENSE

@@ -1,21 +1,21 @@
-MIT License
+    MIT License
 
-Copyright (c) 2022 Microsoft Corporation.
+    Copyright (c) 2022 Microsoft Corporation. All rights reserved.
 
-Permission is hereby granted, free of charge, to any person obtaining a copy
-of this software and associated documentation files (the "Software"), to deal
-in the Software without restriction, including without limitation the rights
-to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
-copies of the Software, and to permit persons to whom the Software is
-furnished to do so, subject to the following conditions:
+    Permission is hereby granted, free of charge, to any person obtaining a copy
+    of this software and associated documentation files (the "Software"), to deal
+    in the Software without restriction, including without limitation the rights
+    to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+    copies of the Software, and to permit persons to whom the Software is
+    furnished to do so, subject to the following conditions:
 
-The above copyright notice and this permission notice shall be included in all
-copies or substantial portions of the Software.
+    The above copyright notice and this permission notice shall be included in all
+    copies or substantial portions of the Software.
 
-THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
-IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
-FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
-AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
-LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
-OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
-SOFTWARE.
+    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+    IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+    FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+    AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+    LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+    OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+    SOFTWARE

README.md

@@ -4,7 +4,49 @@
 <td style="width: 140px; text-align: center;"><a href="https://github.com/devcontainers"><img width="128px" src="https://github.com/microsoft/fluentui-system-icons/78c9587b995299d5bfc007a0077773556ecb0994/assets/Cube/SVG/ic_fluent_cube_32_filled.svg" alt="devcontainers organization logo"/></a></td>
 <td>
 <strong>Development Container Templates</strong><br />
-<i>Example development container configurations, using <a href="https://github.com/devcontainers/images" >devcontainers/images</a> and <a href="https://github.com/devcontainers/features" >devcontainers/features</a>.
+A simple set of dev container 'templates' to help get you up and running with a containerized environment.
 </td>
 </tr></table>
 
+
+A **development container** is a running [Docker](https://www.docker.com) container with a well-defined tool/runtime stack and its prerequisites. It allows you to use a container as a full-featured development environment which can be used to run an application, to separate tools, libraries, or runtimes needed for working with a codebase, and to aid in continuous integration and testing.
+
+This repository contains a set of **dev container templates** which are source files packaged together that encode configuration for a complete development environment. A template can be used in a new or existing project, and a [supporting tool](https://containers.dev/supporting) will use the configuration from the template to build a development container.
+
+⚠️ Development container 'templates' are a
+[**proposed**](https://github.com/devcontainers/spec/blob/main/proposals/devcontainer-templates.md) addition to the
+[development container specification](https://containers.dev/implementors/spec/). **Please note that templates are in
+preview and subject to breaking changes**.
+
+Once the [**proposed**](https://github.com/devcontainers/spec/blob/main/proposals/devcontainer-templates.md)
+specification is accepted, implementation details will be published at
+[https://containers.dev](https://containers.dev/).
+
+## Contents
+
+-   [`src`](src) - A collection of subfolders, each declaring a template. Each subfolder contains at least a
+    `devcontainer-template.json` and a [devcontainer.json](https://containers.dev/implementors/json_reference/).
+-   [`test`](test) - Mirroring `src`, a folder-per-template with at least a `test.sh` script. These tests are executed by the [CI](https://github.com/devcontainers/templates/blob/main/.github/workflows/test-pr.yaml).
+
+## Contributions
+
+### Creating your own collection of templates
+
+The [template distribution specification](https://github.com/devcontainers/spec/blob/main/proposals/devcontainer-templates-distribution.md) outlines a pattern for community members and organizations to self-author templates in repositories they control.
+
+A [GitHub Action](https://github.com/devcontainers/action) is available to help bootstrap self-authored templates.
+
+We are eager to hear your feedback on self-authoring!  Please provide comments and feedback on [spec issue #71](https://github.com/devcontainers/spec/issues/71).
+
+### Contributing to this repository
+
+This repository will accept improvement and bug fix contributions related to the
+[current set of maintained templates](./src).
+
+## Feedback
+
+Issues related to these templates can be reported in [an issue](https://github.com/devcontainers/templates/issues) in this repository.
+
+# License
+Copyright (c) Microsoft Corporation. All rights reserved. <br />
+Licensed under the MIT License. See [LICENSE](LICENSE).