Note: I hope this to be the first in a series of analyses of some of the more esoteric operating systems still in existence. This won't be particularly good as regards legibility, so I hope you won't judge me too hardly on that, for once.
RISC OS, or "Why the hell are people still making this?"
The story of RISC OS begins in 1987, with the British computer company, Acorn. The microcomputer revolution of the late 1970s and early 1980s had served Acorn Computers well, and where many of the competitors in the marketplace had fallen, Acorn still stood strong. The company had obtained a large amount of success with its BBC Micro, an educational computer which had been created in conjunction with the British Broadcasting Corporation's Computer Literacy project. However, with the success of Apple's Macintosh and the Commodore Amiga, Acorn moved towards their own graphical user interface, designing a computer to run their new operating system.
What they came up with was the Acorn Archimedes. The Archimedes was a very powerful computer for its time, using the then-new ARM processor architecture which produced far more calculation per megahertz than the competing Motorola 68000 used in Apple and Commodore's computers. Obviously, a useful operating system had to be built in order to take advantage of the power that the ARM processors provided.
Acorn came up with RISC OS. A co-operative multitasking operating system working from a GUI, it beat the efforts of Apple, who wouldn't move to preemptive multitasking until 2001, or even co-operative multitasking until 1988, and made a mockery of the nascent Windows operating system from Microsoft. Stored in ROM on the motherboard, it was also a very efficient operating system, quick to boot up and to respond.
However, despite a powerful computer and a relatively advanced operating system, Acorn would get nowhere near the amount of success with the Archimedes as it did with the BBC Micro. The x86 platform already had a large amount of the lucrative business market, resulting from years of IBM backing, and Apple had a more elegant design which was popular among designers and artists. Apart from the education sector, the Archimedes found little success, and ended up being relegated to a niche product.
By the time of the release of Windows 3.0, the future was looking increasingly promising for Microsoft. x86 PCs were becoming cheaper and cheaper, with a large amount of competition in the sector, while other computer companies, despite potentially superior computers, suffered from lack of recognition. By 1998, being one of the longest-surviving of the computer companies from the 1980s, Acorn closed down, beaten by a far more popular and far more powerful software platform from Microsoft.
But while the computer division of Acorn had failed at the hands of the all-sweeping Intel x86 platform, the business had more success in the processor division. The ARM processor had one great advantage over most of its competitors, something which made it extremely popular: It used far less power than its competitors. This was a feature which made - and makes - it particularly favoured in embedded systems, where low power consumption is imperative. Your mobile phone will almost undoubtedly use an ARM processor of some kind. Almost all MP3 players use ARM processors, as do the Game Boy Advance and DS handhelds. The processor architecture has found a home in most parts of the consumer electronics industry, from handheld devices to routers and hard drives. (Yes, I know this paragraph is terrible.)
With the success of the ARM processor architecture, it proved to be only a small task to reprogram RISC OS for the newer ARMs. A company named RISCOS Ltd. took up the task of maintaining the operating system for the newer computers, made by Castle Technology Ltd.
The question I have is: Why would you commercially resurrect such an old operating system? To be brutally honest, while RISC OS may have been effective and powerful for the 1980s, there's little to endear it to modern computer users. The OS still has co-operative multitasking, which proved itself obsolete in the mainstream market with the release of Windows 95, and in the computer science industry many years before that. It's tied into a very small line of computers from Acorn and Castle Technology, the former being long obsolete, and the latter being extremely expensive for what you get. Without the ability to implement file extensions, or spaces in file names, naming conventions are extremely odd.
But all of that pales in comparison to the absolute insanity of one the programming languages used in programming the operating system. Two of the languages are perfectly rational and sane: 46% is programmed in C, and 44% is programmed in ARM assembly language. These programming languages are consistent with other operating systems built on the ARM architecture; they aren't made to be portable across to personal computers. It's the third language which is madder than a hat-maker in a bathtub full of mercury: 10% of the operating system is written in BBC BASIC.
Yes, that's right - BASIC, a programming language most commonly known for its ubiquity on 1980s microcomputers and angering Edsger W. Djikstra. What's more, Acorn even originally programmed part of the GUI in it, and while I have to have respect for programmers that could program any sort of working graphical interface in BASIC, I feel strongly that it's the completely wrong language for operating system programming. All of these quirks and more contribute to an operating system which seems to be completely inadequate for modern tasks.
And yet, despite these apparent faults, RISC OS has one major factor in favour of its continued existence. It is probably the single most efficient operating system still being made for personal computers. Still provided on a 4MiB Flash ROM, RISC OS is still amazingly quick, and there's a reason why the operating system has so much assembly language content. In fact, it has to be one of the few operating systems where the more modern version actually runs faster than the older one on systems with the same hardware - and at this point, I point at Microsoft accusingly. Boot-ups in half a minute, immediate shutdowns, an amazing response all around.
The efficiency stretches to the applications as well, where each RISC OS application is far more efficient than its equivalent on Windows, Mac OS X, Linux or the other UNIX-based operating systems being used today.
On that alone, RISC OS deserves to be commended. In an era when operating systems are becoming larger and larger, this is an operating system that has improved its efficiency over the years. Startup takes about fifteen to twenty seconds, and as soon as the GUI is online, it's ready to accept input. Even a clean Windows XP install takes at least a minute to start up on modern technology, and the GUI doesn't immediately accept input. The same is true of Mac OS X and Linux. As an advocate of a quick-booting, quick response operating system for netbooks and educational purposes, RISC OS shows some characteristics which operating system manufacturers should take account of, even if the operating system is fundamentally outdated.