How Android came to be, well, Android

Android is the world’s most popular operating system (OS) for consumers, powering billions of smartphones, tablets, smart TVs, and other devices around the world. While there are many other popular operating systems out there, none have reached as wide a range as Android. The operating system’s success story is long and winding, but today we’re looking back at the true origin story.

Although Google is (rightly) credited with developing Android, the early building blocks of the operating system owe their existence to the similarly ubiquitous but less recognized Linux operating system. Today, Linux distributions include Debian, Fedora, Ubuntu, and many, many others, and power PCs, servers, and Raspberry Pis around the world.

Related: Linux on Chromebooks – How to Install Linux Apps

All of these operating system variants, including Android, go back to an announcement made 30 years ago today, on August 25, 1991, the day Linux inventor Linus Torvalds first revealed, at the age of just 21, that he is working on a new operating system. A project that would later provide the Linux kernel that will be used to build the Android operating system that you might be reading this on.

Hello everyone out there who use Minix –

I’m making a (free) operating system (just a hobby, won’t be big and professional like gnu) for 386 (486) AT clones. This has been brewing since April and is starting to finish. I would like feedback on things that the people of Minix like / dislike as my operating system is somewhat similar to it.

Linus Torvalds – Aug 25, 1991 on the comp.os.minix newsgroup

From Linux to Android

The first public Linux source code was released on September 17, 1991, but Android’s modern journey didn’t begin until much later, in October 2003. Between these dates, Linux was extensively redesigned and transformed from a rudimentary operating system into something more suitable for a modern computing environment . The important thing is that the Linux code base is open source, which helps to garner input from developers around the world and outsource myriad OS forks for purposes ranging from desktop PCs to supercomputers to smartphones.

The development of the operating system we know today has been gradual – the XFree86 graphical user interface came out in 1994, while Linux 2.0 introduced support for multiple processors in 1996. KDE introduced its first advanced graphical desktop user interface for the operating system in 1998, while in 2001 USB devices were finally supported with Linux 2.4. All of these developments are clearly indispensable for desktops, servers and mobile devices. The earliest versions of Android were based on Linux 2.6, which was released in 2003. At the time of writing, your Android smartphone is almost certainly running a Linux kernel based on version 4 or higher.

Android Inc. was founded in 2003, but the decision to use Linux as the basis for a smartphone operating system was only made after the company was taken over by Google in 2005. The Open Handset Alliance was founded. Under the leadership of Google, this 34-person group opted for an open standard for mobile devices, which culminated on November 5, 2007 with the introduction of Android 1.0. Controversially, members are banned from using non-Google forks on Android, which doesn’t feel very much in line with the spirit of Linux’s open source origins.

See also: The story of Android – The development of the world’s largest mobile operating system

Of course, Android bears no obvious resemblance to other popular Linux distributions like Debian or Ubuntu. Android has its own mobile-oriented user interface, an APK app file type, a Java virtual machine to run apps, a bespoke power manager, and tons of other tools built into the operating system that are incompatible with other distributions. That’s all of the extra work that Google has put in over the past two decades to optimize Android for mobile and other devices. Even so, Android still shares a core component and story with other distributions: the Linux kernel.

Why build Android on Linux anyway?

What is this word “kernel” all about? Well, it’s an important building block that is part of an operating system, but it doesn’t include everything. The user interface or bundled software that could make up the parent operating system is not part of the kernel. Instead, the Linux kernel manages hardware resources such as CPU, memory or Bluetooth. You can read more about this in the following article.

Continue reading: Is Android Linux? Or is it more than just a distro deep inside?

This difference to “PC-Linux” was reflected in the fact that Android code was removed from the kernel in 2010 (Linux 2.6.33), so that the two differ somewhat from each other. Instead, Google forked the open source Linux kernel and built it with the features needed to support Android-specific APIs, from the user interface to power management, networking, and security. The two modern Android phones that were reunited in 2012 use the Long Term Stable (LTS) branch of the mainline kernel. In 2017, Google helped the Linux community to extend LTS support from two to six years to ensure a longer update cycle.

But if Android is so different from other Linux variants these days, why should the operating system be built on it at all? Well, there are a couple of very good reasons.

Building a kernel from scratch is extremely time consuming. Linux was and is open source and offers many of the core functions needed to build devices, from supercomputers to mobile devices. Linux 2.6, on which the early Android was based, contained, among other things, a driver layer that enabled product providers to abstract and optimize unique hardware, a robust network stack and toolkit, and process management for allocating app resources. Why spend money and time reinventing the wheel?

Importantly, many of the early advantages of Linux are still relevant to Android smartphones today. For example, the Hardware Abstraction Layer (HAL) enables manufacturers to innovate on the hardware side and has helped Google accelerate the rate of operating system updates. Meanwhile, the authorization-based security model of Linux forms the core of the extensive app authorization system of Android. Even in 30 years, the Linux kernel has proven to be incredibly flexible and powerful.

It’s hard to believe that the billions of Android devices in use today can trace their origins back to Linus Torvalds’ humble UseNet newsgroup post from 30 years ago. Your smartphone may be unrecognizable by this early operating system, but Android remains Linux at its core. It has just formed its own very different branch in Linux’s ever-growing evolutionary tree.