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Much of the content here is a direct port from https://github.com/japaric/discovery

src/background/README.md

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+# Background
+
+## What is a microcontroller?
+
+A microcontroller is a *system* on a chip. Whereas your laptop is made up of several discrete
+components: a processor, RAM sticks, a hard drive, an ethernet port, etc.; a microcontroller has all
+those components built into a single "chip" or package. This makes it possible to build systems with
+minimal part count.
+
+## What can you do with a microcontroller?
+
+Lots of things! Microcontrollers are the central part of systems known as *embedded* systems. These
+systems are everywhere but you don't usually notice them. These systems control the brakes of your
+car, wash your clothes, print your documents, keep you warm, keep you cool, optimize the fuel
+consumption of your car, etc.
+
+The main trait of these systems is that they operate without user intervention even if they expose a
+user interface like a washing machine does; most of their operation is done on their own.
+
+The other common trait of these systems is that they *control* a process. And for that these systems
+usually have one or more sensors and one or more actuators. For example, an HVAC system has several
+sensors, thermometers and humidy sensors spread across some area, and several actuators as well,
+heating elements and fans connected to ducts.
+
+## When should I use a microcontroller?
+
+All these application I've mentioned, you can probably implement with a Raspberry Pi, a computer
+that runs Linux. Why should I bother with a microcontroller that operates without an OS? Sounds like
+it would be harder to develop a program.
+
+One main reason is cost. A microcontroller is much cheaper than a general purpose computer. Not only
+the microcontroller is cheaper; it also requires much less external electrical components to
+operate. This makes Printed Circuit Boards (PCB) smaller and cheaper to design and manufacture.
+
+Another big reason is power consumption. A microcontroller consumes orders of magnitude less power
+than a full blown processor. If your application will run on batteries that makes a huge difference.
+
+And last but not least: (hard) *real time* constraints. Some processes require their controllers to
+respond to some events within some time interval (e.g. a quadcopter/drone hit by a wind gust). If
+this *deadline* is not met, the process could end in catastrophic failure (e.g. the drone crashes to
+the ground). A general purpose computer  running a general purpose OS has many services running in
+the background. This makes it hard to guarantee execution of a program within tight time constraints.
+
+## When should I *not* use a microcontroller?
+
+Where heavy computations are involved. To keep their power consumption low, microcontrollers have
+very limited computational resources available to them. For example, some microcontrollers don't
+even have hardware support for floating point operations. On those devices, performing a simple
+addition of single precision numbers can take hundreds of CPU cycles.
+
+## Development on the micro:bit
+
+The [micro:bit website](https://microbit.org/code/) offers several very simple ways of programming a
+microbit, aimed at teaching school children how to program. This is a very good introduction to the
+world of microcontollers **and** programming, but falls short of teaching true embedded development.
+From there you would usually move to C to develop skills useful in industry, developing performant
+embedded software.
+
+## Why use Rust and not C?
+
+Hopefully I don't need to convince you here as you are probably familiar with the language
+differences between Rust and C. One point I do want to bring up is package management. C lacks an
+official, widely accepted package management solution whereas Rust has Cargo. This makes development
+*much* easier. And, IMO, easy package management encourages code reuse because libraries can be
+easily integrated into an application which is also a good thing as libraries get more "battle
+testing".
+
+## Why should I not use Rust?
+
+Or why should I prefer C over Rust?
+
+The C ecosystem is way more mature. Off the shelf solution for several problems already exist. If
+you need to control a time sensitive process, you can grab one of the existing commercial Real Time
+Operating Systems (RTOS) out there and solve your problem. There are no commercial, production-grade
+RTOSes in Rust yet so you would have to either create one yourself or try one of the ones that are
+in development. If you are looking to develop your skills to find a job, it is currently unlikely
+that a company doing embedded software development will be using Rust, and so your time would be
+better spent learning normal embedded development using C.