Nearly thirty years ago, Linus Torvalds sent out an email announcing the release of Linux, a free operating system that Linus described as “just a hobby” and not something “as grand and professional as GNU.” It can be said that in the 28 years since Torvalds announced the launch of Linux, it has had a huge impact in the tech field and the world at large. Most people are already familiar with the “origin story” of Linux. This article presents 28 facts about Linux (the kernel and its larger ecosystem), some of which you may not know. 1 – Standalone Linux is not very useful, so people started creating Linux distributions that bundle user software with it to make it easier to use and install.The first Linux distribution was Softlanding Linux System (SLS), released in 1992, using the .96p4 Linux kernel. At that time, you could buy it on 5.25-inch or 3.5-inch floppy disks, and if you were a “high-tech enthusiast,” you could also buy it on CD-ROM. If you wanted a GUI (Graphical User Interface), you needed at least 8MB of memory. 2 – SLS did not last long, but it influenced Slackware Linux, which was first released in 1993 and is still in development today.Slackware is the oldest existing Linux distribution, which celebrated its 26th birthday on July 17 this year. 3 – Linux has the largest installation base of any general-purpose operating system. It supports a wide variety of devices, from all 500 of the Fortune 500 supercomputers to Android phones, Chrome notebooks, as well as various embedded devices, Kindle e-readers, and smart TVs (including the laptop used to write this article). 4 – When Linus announced the launch of Linux, what he actually announced was not “Linux” at the time. It was not yet named; he simply said “a free operating system,” quite similar to Minix. A bit like that. Later, the name Linux was derived from “Freax,” a combination of “free,” “freak,” and “x.”How would you feel about a name like “Red Hat Enterprise Freax”? Thank goodness that didn’t happen. 5 – Once the name was established, people had to figure out how to pronounce it. Linus himself provided an audio file on how to pronounce Linux, which is pronounced (approximately) as Leenucks. 6 – Since 1991, it has become a bit “bloated.” The first version of Linux was less than 1MB, uncompressed. The latest stable kernel (as of this writing, 5.2.7) is about 103MB compressed and 946MB uncompressed. Fairly speaking, it can do much more work now than it could in 1991. 7 – Linux was not originally licensed under the GNU General Public License (GPL). The first version included wording that did not allow for charging for redistribution. The first version licensed under GPLv2 was released in December 1992 as version 0.99. Note that this is limited to GPLv2. 8 – You may notice that there are too many choices for Linux. Very, very many. According to data provided by Distrowatch, there are over 850 registered Linux distributions. Over the years, many versions have been phased out. The site currently lists 260 “active” Linux distributions, which of course includes Red Hat Enterprise Linux, Fedora Linux, CentOS, and so on. If you also count variants of major distributions, such as Fedora’s Spins, these numbers skyrocket. At one point, there was even a Hannah Montana-themed Linux distribution. Seriously, this is not made up. 9 – If you have been using Linux for a while, you may remember seeing “Bogomips” displayed during system boot. Bogomips is a measurement of “the number of millions of times a processor can do absolutely nothing in one second.” Sounds silly, right? Indeed, but they are also quite useful. Linux needs a timing loop calibrated to the speed of the machine it runs on, hence the creation of BogoMips. But it is not very useful for many other things, so the name is a portmanteau of million instructions per second (MIPS) and bogus. Now, most systems include a graphical boot screen and do not display Bogomips at all anymore. This is good because the only reason to keep Bogomips is to avoid breaking user space — certain user programs apparently depend on it. If you are curious, you can find your system’s Bogomips by running `cat /proc/cpuinfo | grep bog`. Your CPU has a Bogomips number for each core. 10 – When you boot your computer, Linux is not the first thing that runs. It relies on some bootloader to kick things off, and then hands off to something else to load device drivers and take over the operating system. It’s not as simple as booting from a USB stick or CD-ROM to run the Linux system you want. Over the years, Linux has had a series of bootloaders and has made great strides in booting Linux systems. The admirable Loadlin bootloader could run in MS-DOS and replace the running system to boot Linux. The first version of SLS Linux required a boot floppy disk on every reboot, or you had to try to configure LILO manually. Over the years, we have used LILO, BootX (for Mac), yaboot (also for Mac), the SYSLINUX series of bootloaders (including bootloaders for booting from ISO images or booting over the network using the PXE protocol), the GNU Grand Unified Bootloader (GRUB) versions 1 and 2, and many other bootloaders. 11 – The Linux kernel used to have a versioning scheme: even-numbered versions were for stable kernels, while odd-numbered versions were for development kernels. For example, the 2.2 Linux kernel series was a “stable” series, while 2.3 was an unstable series. Starting with the 2.6 kernel, this scheme changed as they began to try to release new kernels faster and stopped using long development cycles. It took about three years for the kernel to reach 1.0, and just over two years to reach 2.0. It took 15 years for the version numbering to reach 3.0, and then less than five years to release the 4.0 kernel. At this point, version number jumps are not very significant, Linus said: “I don’t read too much into numbers.” 12 – Linux was not portable when it was first written. Linus targeted the 386 (an early Intel chip) and that was it. The first “official” port was in 1995 for the DEC Alpha CPU. The Linux kernel now runs on a multitude of CPUs, but support for the 386 itself was dropped in 2012. 13 – Linux has thousands of contributors. In 2016, the Linux Foundation confirmed that from 2005 to 2016, there were 13,594 contributors, and counted over 22 million lines of code in its kernel. This does not account for contributions before 2005. 14 – Most Linux enthusiasts have heard of the kernel’s official mascot, Tux. Many do not know that Tux was officially retired during the 2.6.29 kernel cycle and replaced by Tuz.
Tuz is a Tasmanian Devil, or a Tux dressed in a Tasmanian Devil costume, chosen to raise awareness of the endangered status of the species. Attendees at the 2009 Linux.conf.au conference received a stuffed Tuz toy, while the traditional Linux.conf.au charity auction raised about 40,000 Australian dollars for the campaign to save the Tasmanian Devil. (Image by Andrew McGown and Josh Bush. Image licensed under CC BY-SA.) 15 – One of the first worms targeting Linux (if not the first) emerged in January 2001. The Ramen worm targeted wu-ftpd, nfs-utils, and lprng, and as a precursor, we will see more attack attempts triggered by the popularity of Linux, including the creation of worms, viruses, and other attacks targeting Linux. 16 – The New York Stock Exchange (NYSE) switched to using Linux to run critical systems in 2007. 17 – If it weren’t for Linux, there might not be Git. Linus Torvalds created Git for developing the Linux kernel because he was dissatisfied with the version control systems available at the time. Thus, Linux not only spawned a vast ecosystem around the operating system, but also laid the foundation for the core of today’s most widely used and popular social development platform. 18 – There was a time when Apple sponsored a project to run Linux on the Mach microkernel based on the Power Macintosh platform. This seems to be Apple’s first official foray into open source software, predating the announcement of Darwin in 1999. The first version, known as MkLinux, was co-developed by Apple and the Open Group Research Institute in France. It debuted at the 1996 Worldwide Developers Conference (WWDC), but never gained popularity. By 1998, it became a community-led effort and remains a niche endeavor within the larger Linux ecosystem. 19 – Before Google emerged, finding content on the internet was quite challenging. In 1998, some enterprising Linux enthusiasts built a “Linux search engine” to help users find information about Linux distributions, Linux user groups, and other Linux-related information. Unfortunately, the content of that search engine (more precisely, a directory) has faded away over time and due to information aging. 20 – Android brought Linux to countless people’s phones, but it was not the first mobile operating system to feature the Linux kernel. That honor arguably belongs to the Motorola A760, launched in 2003, which came with a video player, music player, instant messaging tools, and other goodies. 21 – The first commercial Android product shipped was the HTC Dream, in September 2008. This phone had a physical keyboard, a mini trackball, and a “cool” 320×480 resolution. Smartphones have improved significantly in the 11 years since, but some of us still have a soft spot for physical keyboards. 22 – The first public version of Red Hat Linux was released during Halloween in 1994. It was a beta (0.9) version with the 1.0.9 stable Linux kernel, or if you were feeling adventurous, you could use the 1.1.54 development kernel. (And let’s face it, if you were using Linux in 1994, you were adventurous!) 23 – As we mentioned earlier, Linux has expanded significantly since its inception. It is used for a dazzling array of workloads, from driving consumer devices like e-readers to running AI/ML (artificial intelligence/machine learning) workloads on massive clusters. But did you know there is a Linux orchestra? The Linux Laptop Orchestra (L2Ork) is a “laptop orchestra” from Virginia Tech’s Digital Interactive Sound and Media Studio (DISIS). L2Ork is described as a “contemporary media ensemble” that “combines traditional ensembles with increasingly accessible human-computer interaction technologies to explore gesture, community interaction, and multidimensional artistic expression.” If that description drives you crazy, you can watch a video about L2Ork on YouTube and enjoy the melodic sounds of Linux. 24 – If orchestras are not your thing, you can enjoy a little pastoral scenery through Linux. It really is pastoral scenery. Over the years, one of the unexpected workloads for Linux has been… milking cows. DeLaval’s “Voluntary Milking System” (VMS) allows cows to decide when to be milked and manages the process without human intervention. All this work is managed by a single board computer (SBC) running Linux. 25 – If you like lightweight and affordable laptops, you might want to thank Linux a little. The launch of the Asus Eee PC (netbook) can be said to be a factor driving down costs and drawing attention to lighter, more portable machines. The Eee PC is a lightweight, compact, and inexpensive (priced under $300) “netbook” that debuted in 2007. The keyboards on the first models were smaller than regular keyboards, so if your fingers are thicker than average, good luck with that. Importantly, the Eee PC came with a custom Linux distribution, meaning it did not carry a “per-unit” cost for the operating system itself. Netbooks were eventually phased out by devices like tablets, smartphones, and Chromebooks. But it was an interesting experiment made possible by Linux. 26 – Installing Linux is not always easy. But it can be entertaining at times. Back in the day, when disk speeds were slow and installers asked many questions, the Caldera OpenLinux installer would display a game similar to Tetris that you could play while copying to the hard drive. Unfortunately, the Red Hat Enterprise Linux Anaconda installer did not offer Tetris or any other games. This is not a big deal because installing Linux on modern hardware is typically much faster than it was with CD-ROMs and slow hard drives in the past. 27 – It is well known that Linux has been widely used in film production in recent years. If you are watching a movie with a lot of CGI (computer-generated imagery), it is quite possible that the rendering of that movie was done on Linux. At least according to public records, the first blockbuster to use Linux was “Titanic”. Digital Domain used a network of 200 Alpha machines running Red Hat Linux to accelerate the rendering process. 28 – The Linux kernel is not released on a set schedule, so if you need to predict when the next kernel version will be released, how would you do it? Guess with a crystal ball? According to the “PHB Crystal Ball” website, the average development time for a kernel is 68 days, with a merge window period of 13 days. According to that site, the next kernel release is expected to be on Sunday, September 19, 2019. Happy 28th birthday, Linux!
The history of Linux is full of fascinating facts and stories, so this article is just a glimpse of that history. As they say, the best is yet to come. Just as Linux’s past is interesting and impressive, its future is equally promising. Happy birthday, Linux! A bright future ahead!
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