Imagine for a moment that: there is no such thing as the Windows operating system; Mac OS X… no one heard of it; we don’t have any Linux distributions to play around with – while Android and iOS are nowhere to be seen.
Now let’s travel to the famous Bell Laboratories: it’s 1969 and we witness the birth of something which will forever change the way people interact with computers.
UNIX begins
Way before the Tux penguin came to life, more exactly in 1969, two bearded guys created something that would eventually become a standard in the server world, and the starting point for some of the top operating systems in history: UNIX (Uniplexed Information and Computing System).
In order to better understand the importance of UNIX, we must first consider that, back in the days, a computer was the size of Texas (ok, maybe not that big!), and each computer needed its own individual operating system in order to function.
This big inconvenient was tackled by Ken Thompson and Dennis Ritchie (among others), and soon a new operating system saw the light of day. After 4 years, in 1973, UNIX was rewritten in C, a move which represented a pivotal moment in its history, making the new operating system portable.
Let’s dig deeper
Right now, UNIX and its derivatives are used by 67.1% of all websites (whose operating system we do know), an impressive figure for such an old operating system. But what stands behind this achievement? Well, the UNIX operating system relies upon 3 major pillars:
Kernel: It’s the core of the operating system, it interacts directly with the hardware and contains subsystems such as: process management, file management, device management, network management, memory management. Also, it handles interrupts from hardware devices.
Shell: The shell acts as an interface to the OS, it allows users to interact with the kernel and to run programs. The shell is a command line interpreter (yes, the much dreaded command line! …at least by some users), it takes the commands given by the user and translates them to the kernel. Basically, it takes human language and transforms it into machine language, 01100001 01110111 01100101 01110011 01101111 01101101 01100101! (awesome)
Commands and Utilities: These are the commands which can be used by the user to interact with the operating system. There are over 400 standard commands (alongside 3rd party ones), commands such as: cd, cat, grep etc.
For those of you who are not at all familiar with UNIX, the following list might shed some light on some of the top UNIX characteristics and advantages:
1. Multi-user – multiple users can use the machine at the same time
2.  Multi-tasking with protected memory– multiple programs can be run at the same time
3. Portability – only the kernel (less than 10%) is written in assembly language
4. Very efficient virtual memory
5. Unified filesystem
We can’t however get past some of UNIX’s weak points, such as:
1.  Casual users won’t find their way in UNIX
2. It has a steep learning curve
3. It easily allows for severe mistakes
Final considerations
All in all, UNIX seems to be oblivious of its own age, showing us that old is not obsolete. Although in recent years it suffered a decline in market share, UNIX still has the power to sustain millions of computers all around the world, with great success.
The future of UNIX however is unsure, and some analysts are predicting that in the following years UNIX is going to see its end of life. If this proves to be true, then it makes sense for it to be replaced by another operating system, right?
We talked about the uncertain future of UNIX and a possible replacement, and as most of you probably guessed (it was not that hard, after all), Linux is often seen as the operating system which has what it takes to become the next UNIX (more on this at the end of the series). Considering this to be true, let’s see how the lovely penguin broke the ice.
Linus Torvalds starts low
The first mention about Linux was made by Linus Torvalds in 1991. The Finnish software engineer confirmed his interest in the standard POSIX definition, without revealing the name of his MINIX project.
Many projects started with high expectations and now they are long-forgotten. Linux had one of the humblest beginnings, but it was the one which eventually made history. If you think that this is just wordplay, keep on reading!
No matter the reason behind Linus’ determination to create a new operating system kernel, we are both glad and thankful that he made that call. The kernel’s first version, namely 0.01, resembled the MINIX model and was released for i386(+) AT-machines. Also, the Linux variant did not use any code from other sources, although at that time it needed MINIX to run.
Created in 1987, MINIX derives from mini-UNIX. It was developed by Andrew S. Tanenbaum as an operating system with a microkernel architecture. Although Linux employed a monolithic design, while MINIX used a microkernel, Torvalds was a fan of Tanenbaum’s design concepts. As for the main reason why Linux needed MINIX to run properly, it was due to the fact that development was done on this host system. Among others, Linux’ file system has taken its inspiration from MINIX.
With the backing of the open-source community, the Linux kernel grew to version 0.95, which was capable of running the X Window System). Around the same time, the first three major distributions (or distros) arose and they would become the starting point for many other distros – plenty of them available right up to this day.
Linux sets off
Slackware, Debian and RedHat are without a doubt the three distros that have shaped the future of Linux. The first of the trio was Slackware, which spawned from SLS (a buggy albeit advanced distribution, 1992). The next distro to see the light of day was Debian, created by Ian Murdock in 1993 (named after Ian Murdock himself and his girlfriend, Debra Lynn). Last but not least, Red Hat, was developed by Marc Ewing in 1994 – the distro which would eventually climb to the top of the ladder in the world of server operating systems.
Out of the three, the first to really take off was Red Hat, with distros such as Mandrake, Caldera, TurboLinux, Red Flag – all of which were based on Red Hat. Debian-based distros came along, too, being more desktop-oriented than Red Hat as well as more user-friendly.
While more distros gained popularity, around 1996, version 2.0 brought features such as SMP support, better memory management, while more processor types became compatible the Linux kernel.
The first week of 2000 marked the start of the longest active kernel version, specifically 2.4, which was supported until 2011. The new version offered compatibility with USB, PC Cards, ISA Plug and Play, and went on to add Bluetooth, RAID and EXT3 support on its list.
It’s all about the desktop!
In 1996, Matthias Ettrich founded the Kool Desktop Environment (KDE), a full-blown desktop environment, which could be installed for any Linux distribution, starting with 1998. Also, around the same period, Miguel de Icaza and Federico Mena developed another desktop environment, Gnome, which became a user-friendly and fast environment in a short amount of time. The first distro to use Gnome was none other than Red Hat.
Having a solid and reliable kernel, a growing desktop environment, and the full support of the open-source world, beginning with the year 2000, the operating system started to grow exponentially. As of January 2017, the number of active distros on Distrowatch was 286, meaning that we have 286 Linux distributions to choose from – and that is not bad at all.
This is where the second part of the article comes to an end (but do not forget to return for the final part). Until then, feel free to share with us your love for the Tux penguin!
As detailed above, the number of Linux distros has increased rapidly, as the Open Source community responded in a positive manner to the flexibility of the Linux kernel. Now, let’s move on with our review!
It is still about the desktop!
In January 2017, the number of active distros stood at 286. Nevertheless, as far as I can see, only a few of them can be considered serious contenders for the desktop environment, dominated by Windows and Mac OS X.
People have their own preferences, so there is no point in disputing them. Considering this, here are some of the most interesting Linux flavours for desktop PCs. It is up to you to decide which one suits your needs best. Disclaimer: I am all for Elementary.
Ubuntu: it is forked from Debian, it is ranked third on DistroWatch (at the time of writing this article), and it offers a lot of software packages.
Mint: being spawned from Ubuntu, it currently holds first place on DistroWatch. Most people are enjoying it because it has a beautiful and user-friendly interface.
OpenSUSE: the lizard derives from Mandriva and it ranks in fourth place on DistroWatch. Although it does not have the best-looking interface, it has loads of software packages and the YAST tool is simply stunning.
Elementary OS: this little distro has Ubuntu roots and, although it holds the sixth place on DistroWatch, it is one of the best-looking Linux-based operating systems. Its UI is user-friendly, thus forcing Windows/Mac users to remove one complaint from their list of reasons against making the move to Linux.
Linux goes mobile, hits the jackpot
It all changed on September 23, 2008, as this was the release date for the most successful mobile operating system of all time: Android. Developed by Google and based on the Linux kernel, Android managed to achieve a mobile market share above 86% during the third quarter of 2016, according to IDC, – an impressive accomplishment, to say the least, especially since both Apple and Microsoft have been unable to put a dent on its market share for so many years.
Android’s kernel uses the long-term support branch of Linux and, since 2014, it uses versions 3.4 or 3.10 of the Linux kernel. It is obvious that Android has some architectural changes, but Linus Torvalds has stated numerous times he is hopeful that Android and Linux would return to a joint kernel in the foreseeable future.
Taking over the cloud
Nowadays, we have some great desktop operating systems and a highly-popular mobile OS, all based on Linux. However, let’s not forget the strongest case for Linux: servers. Here are some quick figures that show how big Linux really is:
- As of November 2016, 498 of the world’s 500 fastest supercomputers run some variant of Linux;
- six of the top 10 internet hosting companies are powered by Linux;
- in 2014, 75% of the cloud solutions used Linux;
Some of the key points for Linux’ success can be attributed to several things, including:
- Security: out of the box, Linux has proven to be very safe;
- Stability: it can handle large number of processes without crashing, most configuration changes do not require restarts;
- Open-Source: you’re free to do with the operating system as you like, customizing it based upon your needs;
- Performance: Linux for servers is fast and scalable, you can make it run on the lowest hardware requirements that you can think of;
- Free: all-in-all, it is free, and although there are costs involved in regards to maintenance, Linux and all software in it are free.
As a display of Linux’ prowess when it comes to servers, IBM and Canonical have worked together on a special project. As of September 2016, you can use Ubuntu on IBM machines, including z Systems Mainframe. When IBM wants to use your operating system on their machines, then you know that you are on the right path.
A brighter future waiting around the corner
No one would have imagined in 1991 that Linux would become the leading solution in both cloud and web services. Unfortunately, the operating system did not quite get a grip on the desktop market, as StatCounter data reveals a market share of only 0.94% for the year 2016. Thankfully, the penguin OS has a more significant presence in the server and mobile markets.
The Internet of Things is said to become a catalyst for Linux’ future. Usually, IT-related predictions are laughable once several years pass them by, so it is wiser to refrain from making assumptions. For the time being, Linux cannot become a serious contender in the desktop PC world against Windows and Mac OS X, unless backed-up by proper software.
Disclaimer: I’ve said in the beginning that Linux can be the perfect replacement for UNIX, but this does not mean that UNIX is going to disappear altogether from the scene. Also, I am aware that Linux is an UNIX-like OS, so technically, UNIX will live through Linux, right? Right?
