docs/os/introduction.md

## Introduction

### Welcome to Apache Mynewt

Apache Mynewt is an operating system that makes it easy to develop
applications for microcontroller environments where power and cost
are driving factors. Examples of these devices are connected locks,
lights, and wearables.

Microcontroller environments have a number of characteristics that
makes the operating system requirements for them unique:

* Low memory footprint: memory on these systems range from
8-16KB (on the low end) to 16MB (on the high end).

* Reduced code size: code often runs out of flash, and total available code size ranges from 64-128KB to 16-32MB.

* Low processing speed: processor speeds vary from 10-12MHz to 160-200MHz.  

* Low power operation: devices operate in mostly sleeping mode, in order to conserve
battery power and maximize power usage.

As more and more devices get connected, these interconnected devices perform complex tasks. To
perform these tasks, you need low-level operational functionality built into the operating system.
Typically, connected devices built with these microcontrollers perform a myriad of functions:

* Networking Stacks: Bluetooth Low Energy and Thread

* Peripherals: PWM to drive motors, ADCs to measure sensor data, and RTCs
to keep time.

* Scheduled Processing: actions must happen on a calendared or periodic basis.

Apache Mynewt accomplishes all the above easily, by providing a complete
operating system for constrained devices, including:

* A fully open-source Bluetooth Low Energy stack with both Host and
Controller implementations.

* A pre-emptive, multi-tasking Real Time operating system kernel

* A Hardware Abstraction Layer (HAL) that abstracts the MCU's
peripheral functions, allowing developers to easily write cross-platform
code.

<br>

### Newt
In order to provide all this functionality, and operate in an
extremely low resource environment, Mynewt provides a very fine-grained source
package management and build system tool, called *newt*.

You can install *newt* for [Mac OS](../newt/install/newt_mac/), [Linux](../newt/install/newt_linux/), or [Windows](../newt/install/newt_windows/).

<br>

### Newt Manager


In order to enable a user to communicate with remote instances of Mynewt OS and query, configure, and operate them, Mynewt provides an application tool called Newt Manager or *newtmgr*.

You can install *newtmgr* for [Mac OS](../newtmgr/install_mac/), [Linux](../newtmgr/install_linux/), or [Windows](../newtmgr/install_newtmgr/).

<br>

### Build your first Mynewt App with Newt

With the introductions out of the way, now is a good time to [get set up and
started](get_started/get_started/) with your first Mynewt application.

Happy Hacking!