docs/blueprints: Add an introduction for Blueprints

Describe the purpose of a blueprint in All Scenarios OS to set
the right expectations.

Signed-off-by: Amit Kucheria <amit.kucheria.ext@huawei.com>

docs/blueprints/index.rst

@@ -5,10 +5,40 @@
 All Scenarios OS Blueprints
 ###########################
 
-This section details the available blueprints provided as part of the
-All Scenarios OS environment.
+Overview
+********
+
+All Scenarios OS integrates its various components into a representative use-case called a `Blueprint`. A blueprint shows off the OS capabilities and best practices in building software-based products.
+
+To this end, blueprints are a way to distill real-world products into a ``minimum viable product`` to demonstrate how partners and users may adopt All Scenarios OS securely in their own products.
+
+What is a Blueprint?
+--------------------
+#. It shows off a key feature or two of the product it is trying to emulate.
+#. It focuses on reproducing a representative user interaction for a use case.
+
+   .. note::
+      Examples include:
+      * A secure network link, e.g., a TLS connection to avoid transmitting plain-text data.
+      * Wireless communication, e.g., via Bluetooth, OpenThread or NFC.
+      * Touch input, e.g., via a keypad or touchscreen.
+      * Display, e.g., showing useful messages on a display.
+      * Autonomous communication between two devices over a wireless link.
+
+#. It is implemented on the closest appropriate reference HW platform from All Scenarios OS.
+
+What a Blueprint Isn't?
+-----------------------
+#. It doesn't try to implement every feature of a contemporary product category in the market.
+#. It isn't optimized for cost, size, or physical looks.
+#. It doesn't try to replicate the physical form-factor of a contemporary product category. Do not expect to see everything hidden away in a pretty enclosure. Expect to see boards and wires connecting to peripherals.
+
+Blueprints
+**********
+
+This section details the available blueprints provided as part of the All Scenarios OS environment.
 
 .. toctree::
    :maxdepth: 1
-   
+
    smart-panel