fixup! Rewrite the introduction to thin-edge concepts

docs/src/understand/index.md

@@ -1,5 +1,5 @@
 ---
-title: Understand the Concepts
+title: Concepts
 tags: [Concept]
 sidebar_position: 2
 ---
@@ -10,8 +10,8 @@ Thin-edge is an open-source IoT development toolbox
 designed to ease the development of smart IoT agents
 with a versatile set of ready-to-use software components
 that can be easily combined with application-specific extensions.
-Thin-edge simple yet flexible extension points enable custom functionality to be added in a modular fashion
-reducing the development efforts significantly.
+
+## What
 
 IoT agents typically run on the edge, at the frontier between IT cloud computing and OT industrial equipment.
 They act as gateways between the cloud and the devices embedded into smart equipment, machines or plants.
@@ -22,12 +22,13 @@ The main functions and challenges are to:
 - process data with local analytics tools and push the relevant subset to the cloud
 - monitor, configure and update agents and the attached devices from the cloud.
 
+## How
+
 To implement these functions, thin-edge proposes to design an IoT agent using a combination of software components,
 which are deployed on the main gateway device as well as the set of interconnected embedded devices that form the equipment.
 
 A typical thin-edge setup consists of the following components:
-- a local MQTT broker, currently [mosquitto](https://mosquitto.org/),
-  that is used as a message bus between all the components of the equipment
+- a local MQTT broker that is used as a message bus between all the components of the equipment
 - an MQTT bridge connection between the local message bus and the remote cloud end-point
 - thin-edge (out-of-the-box) device management services which provide features such as monitoring, configuration and software management
 - equipment-specific services that interact with the hardware that make the equipment,
@@ -52,6 +53,17 @@ These features are implemented by composable software components that:
 - provide the foundation to start the development of an agent with sensible defaults
 - on top of which the specificities required by smart IoT agents can be incrementally implemented
 
+## Why
+
+The aim of thin-edge is to reduce the development effort to build smart IoT agents
+without compromising on quality and feature completeness.
+
+- ready-to-use components provide sound foundations
+- interchangeable software components make it possible to adapt the generic agent to specific contexts
+- simple, yet flexible, extension points enable custom functionality to be added in a modular fashion
+
+## Who
+
 The flexibility of thin-edge means that it can be used at different levels.
 - As a beginner, the simplest option is to use thin-edge as a pre-assembled agent,
   ready to be installed on a device and configured for a cloud account.