Linux was developed by Linus Torvalds. He released it on August 25th, 1991, making the operating system 25 years old today. At the start, it was a “completely personal project,” Linux.com reports Torvalds told LinuxCon today.
Now an open-source project that anyone can contribute to, Linux has grown to 22 million lines of code. At the start, it was just a 10,000 line kernel. The first version of Linux couldn’t boot from any other model of hard disk than the one in Torvalds’ personal computer. He hadn’t considered that other people would want to use his new OS.
The Linux of today supports practically every hard drive in existence. More significantly, it runs on practically every kind of processor architecture in existence, covering 80 distinct families. A far from exhaustive list includes smartphone, tablet, desktop PC, server and tiny embedded platforms.
Linux hasn’t really achieved mass consumer popularity. Most people still think of Windows or Mac OS X when asked to name an operating system and it’s true that Linux is installed on a minority of desktop PCs. However, none of this is to say that consumers don’t use Linux. You almost certainly encounter it on a daily basis, even though you may never have heard of it.
The majority of web servers, services and apps run on Linux. Light, fast, versatile and scalable, Linux has proven to be the operating system of choice for most datacentre environments. It powers millions of websites across the Internet, including infrastructure that makes the web possible.
If you own an Android smartphone, you also own a Linux device. As with the majority of other operating systems, Android is based on the Linux kernel. Even Apple’s Mac OS X can be traced back to a common origin. Linux has grown from a 10,000 line experiment into one of the most widespread operating systems ever built, despite most of its achievements being hidden from public sight.
“Linux started its journey as a platform for researchers and developers and over the last 25 years it has become the innovator’s production platform across all computing platforms we use today,” said Canonical, creator of the Linux-based Ubuntu operating system. “Perhaps it is fairer to say that the world has become developer-led, and since Linux is the first choice of developers, the world has adopted Linux by default. Servers, mobile, IoT and more all primarily run on Linux because the developers who make the most interesting things generally start on Linux.”
Anyone can contribute to and build on Linux, which explains how it’s made its way into projects ranging from Android to the Raspberry Pi. Over 5,000 developers and 500 companies now develop changes for new versions of the Linux kernel. Under its GPLv2 license, all changes have to be made available to all other contributors. Torvalds described this license as a “defining factor” of Linux, helping the operating system avoid fragmentation by requiring all code to be shared.
Today, Torvalds has very little involvement with actually writing code. He no longer contributes to the kernel and very rarely approves changes. Instead, he takes responsibility for overseeing the release process, ensuring new versions are shipped every nine to 10 weeks without fail. The process has proved to run seamlessly in the past few years, although there was a time fifteen years ago when the release procedures were a chaotic mess.
Torvalds orchestrated a restructuring of the community to get everything into order. The code was at risk of becoming fragmented and approving and applying changes was a nightmarish chore. The project switched to the Bitkeeper version control system, which greatly helped with organisation. Later, Torvalds built Git when Linux needed to be scaled up again. Today, Git is one of the most popular version control systems amongst all software developers.
Without the dramatic reorganisation, Linux may never have become what it is today. Its reliable release schedule makes it an ideal base for other projects. The availability of an open-source operating system kernel allows developers to innovate without having to reinvent the wheel. Linux can easily be adapted to build any kind of operating system, whether it be a mobile platform or supercomputer controller.
That defining scalability hasn’t yet been replicated by any other operating system kernel. Its open nature lets anybody innovate on Linux, regardless of their background. These unique characteristics look set to allow Linux to hold its place as the largely unknown behind-the-scenes worker well into the next 25 years.
