A revolutionary idea was to have multiple terminals, all operating simultaneously as if the single computer were divided up in parts. Such multitasking or timesharing is of course done by giving each task a slice of computer time when needed. Pressing a key would send an interrupt to deviate the processor from what it was doing, and to service the user behind the terminal. This posed many challenges, such as how to design an interrupt system, and how to let hundreds of tasks communicate with one another in an orderly way without causing lock-ups and other unwanted side effects.

From this effort the UNIX operating system was born. During the same time, studies also focused on how to make programs, compilers and operating systems 'portable' from one brand of computer to another. The C computer language did this, and it has since been the workhorse for all related development. This made Unix portable to all known mini computers.

In the nineties, Finnish born Linus Torvalds hit upon another idea: what if such a powerful operating system became available entirely free of charge, put together by hundreds, nay thousands of volunteers? It would be truly revolutionary, and he pulled it off. But he started very late in the game, so that the early nineties did not provide for a finished product. Now we are over a decade later, and the Linux development has been able to keep up (just) with new technological developments in order to offer today, a solution that rivals the best of Microsoft. Things are motoring now!

The Linux concept follows that of Unix, to make the power of one computer available to many users. To give you an idea, a standard box bought today would have enough power to connect 200 terminals rattling away all day, doing data input and word processing and printing. Just imagine how much computer power is wasted by your own box!
By contrast, the PC was uniquely wrong-designed to provide the cheapest solution for a single-user computer. This has created a lasting conflict between Linux and Windows. Modern microchips however, had the right architecture to allow for multi-tasking. But the user interface is sheer madness: consider what was once one terminal, keyboard and screen integrated with a pointing device like a track ball, and this compact unit connected over four wires with the computer, often by telephone. Such terminals ran satisfactorily over a 'thin' connection of no more than 9600 bits/second, which could be done by simple postoffice modems.
Since the PC, these integrated 'dumb' terminals have become disconnected: a VDU connects through a super fast cable to a display processor which connects directly to an allocated part of the computer's memory. The keyboard has a predictable 4-wire connection, but the mouse has a separate connection. Why? It is all because of ad-hoc ideas lacking standards.

Now this mess needed to be mopped up so that the KVM (Keyboard-Video-Mouse) once again becomes an integrated device from the operating system's point of view. This is called Xterminal, and in principle Linux can run many Xterminals to the same computer. They could even be networked. So, contrary to Windows, Linux is a multi-user multi-tasking operating system.

Although the number of computers using Linux is small compared to Windows, it must be remembered that Windows runs only on one make of chip: Intel. By contrast, Linux runs on all available CPUs, including super computers. By this measure it is the most widely implemented operating system known. Of course there is UNIX, but development in UNIX has stagnated as far as new hardware is concerned. UNIX is equally portable as Linux, if only it had all the drivers required by modern computer boxes.

In the meantime, the WYSIWYG (What-You-See-Is-What-You-Get) GUI (Graphical User Interface) became hugely popular, soon to be part of all operating systems. Here is where various versions of Linux branched off. There was Corel-Linux with an admirably friendly implementation, which would later become Xandros with KDE. There were the Gnome implementations (GNU Network Object Model Environment) and there was KDE (Kommon Desktop Environment). At the moment these two GUIs are moving closer together, both from the software's and the user's perspective.

Users unfamiliar with Linux may think that the GUI does not measure up to that of the Microsoft operating systems, but how surprised they will be. The Linux desktop does not only look and feel like Windows, it is also much more configurable. Imagine that you can make it look and feel like Windows95, WinXP, MacOS, and other operating systems - just choose. What's more, it offers you a number of virtual desktops, which enables you to group your work efficiently. For instance, a secretary may have one desktop for the computer-controlled phone system, assisted by address and appointments books. The next desktop is dedicated to wordprocessing and spreadsheets, and a third desktop to accounting and data entry. To switch from one desktop to another takes less than one second.

The number of packages available for Linux is sheer mind-boggling: freshmeat.net counts over 21,000 software branches of OSS/FS software as of October 2002.  Sourceforge.net hosts 55,424 OSS/FS projects all by itself (as of January 28, 2003). The Debian stable debian.org hosts over 18,000 packages, and there are many suppliers of non-free or partially non-free software.

Because the software is free, there is no pressure to release it before it is really ready just to achieve some sales target. Every version of Linux is declared to be finished only when it is actually finished, which explains why it is so solid. The other reason why free software is better is because the personal reputation of the developer is attached to every release." - Linus Torvalds, Linux creator

"Contrast this with proprietary software, where we do all begin from scratch -- I believe we could soar, if only we could freely share and build upon the ideas and labours of others. " - anonymous

For an extensive and objective appraisal of Linux, complete with hard data, read http://www.dwheeler.com/oss_fs_why.html

We expect most readers of this paper to be well aware of Linux's obvious positives. From Unix, we have the most successful and time-tested OS architecture ever. We have a development community at least an order of magnitude larger than those of all proprietary OS vendors combined.

A pilot project in the Hanstholm municipality determined that switching the office suite from Microsoft Office to OpenOffice.org and StarOffice did not increase their number of problems and that each user only needed 1 to 1.5 hours of training to learn the new office suite. The municipality will now use OpenOffice.org and StarOffice on all workplaces (200 in all) and will save 300,000 Danish Kroners (about 40,000 Euros) each year in license fees.

There are, however, two distinct Linux stables, based on how they install and manage packages. The oldest of these uses the RPM (RedHat Package Manager) whereas more recent versions use Debian (named after Deb and Ian Murdock, 1993).
The Debian concept is one of extreme professionality and standardisation, setting very high standards of programming, documentation, testing and packaging. For professionals like me, it is the method of choice, and I would guess that businesses would make the same choice. Debian packages go through three stages of reliability: unstable, testing and stable, a transition that may take two years. This does not turn programmers away, rather to the contrary, attracts them, since programmers, like artists, are self-motivated to produce to the best of their abilities.

Another reason for selecting Debian over other distributions is its sheer size of the project (with 18,000 packages) which strongly suggests that Debian won't suddenly disappear and one is suddenly left without any support. Debian can't go bankrupt. Visit www.debian.org to be impressed!

What it all means is that 'stable' Debian packages install without any problems, as they install themselves also in the menu system. But these packages are not the latest versions, and for the more adventurous users, the testing and unstable versions are always available.

"There is more to an operating system than a kernel with a hodge-podge of software thrown on the top -- systems integration is a topic usually given short shift when discussing the merits of a system. But a well-integrated system -- where each piece dovetails with and accommodates other parts of the system -- has greatly increased utility over the alternative." - about Debian

"Debian, in my experience, and the experience of a number of my respondents, is the best integrated OS out there. Debian packages trace their relationships to each other not merely through a flat dependency/conflicts mechanism, but a richer set of nuanced relationships"

• reliability, stability: perhaps most Windows users who make the move to Linux, do it for reasons of stability. You can't help it, but as time passes, a windows operating system becomes more unstable, eventually requiring it to be rebuilt from scratch. But this depends on the amount of software added. Linux does not appear to suffer from instability, except when 'unstable' packages are tried. IT managers save much time because of this.
• scalability: very often overlooked, Linux can be scaled up or down in size, to work on the smallest of PalmTops, to the largest of enterprise servers. It can be scaled to suit schools, or Chinese scholars; home users, professionals, businesses or multinational companies; movie makers and animators; artists and designers.
• efficient, powerful, fast: Linux makes the best use of memory, disk and CPU. It makes your PC seem bigger and faster.
• security: Linux does not suffer from secret back doors, spyware, worms and viruses. It is strict about passwords an privileges.
• complies with standards: Linux relies entirely on well-documented standards, as opposed to Windows who rely on market exclusion with poorly documented proprietary de-facto 'standards'.
• open software: Linux relies entirely on open software or 'peer-reviewed' software which is entirely free. But non-free software of special products is becoming more common.
• intuitive, standard user interface: the graphical user interface (GUI) or desktop is as intuitive as that of Windows, but more functional.
• large library of software: the library of software (packages and modules) exceeds 18,000 items and is still growing.
• easily upgradable: the package managers make installing and upgrading software appear as if all 18,000 packages are already part of your computer. A fast internet connection (like broadband) is advisable.
• networking, servers: Linux has always had a strong market position with its servers (for the Web and for Enterprise), as these are preferred for their reliability and high performance.
• save money: because there are no licensing costs, the savings for enterprises are large, even though one may need to buy a packaged distro, some service and some non-free packages.
• big company support: already for years, IBM has based its efforts on Linux for all its Reduced Instruction Set Computers (RISC) and larger hardware. The new MacOSX is based on Linux. Novell has acquired Suse-Linux which complements its networking offerings. HP has also invested heavily in Linux.
• development software, compilers: all development software like compilers are freely available, such that the programs and packages made with them do not incur costs or licences.

• unsupported hardware: because most hardware suppliers are in binding agreements with Microsoft not to supply to others, a number of hardware devices have remained unsupported. But the Linux community often manages to write drivers by 'reverse-engineering'. Check your hardware out or do a trial installation to find out whether there are any problems.
• proprietary software: if your work depends on proprietary software that won't run on Linux, you may need to give Linux a miss. However, at an accelerating rate, more and more Windows applications begin to run under wine (windows environment) or CrossOver Office.
• playing fast games: Linux prevents direct access to the actual hardware, and is thus bound to be slower for fast games. The good news is that gaming consoles like PlayStation and XBox are cheap and give very good value for money, which relieves the computer from this requirement.
• book/printing industry: the book printing and designing industry relies heavily on the Apple Mac with its Adobe software, and this does not run well on Linux, even though the Mac's operating system is based on Linux. Note that this is all proprietay software.
• proprietary file formats: some proprietary file formats are not free to use, and related software can therefore not be distributed free of charge without breaking copyrights. Such formats are: MP3 music playback, content-protected DVD viewing, AAC and WMA download, PDF, WMV audio/video, Quicktime  Adobe video, Flash Video. But these are often provided as free plugins for web browsers.

• is Linux more compact? In theory, Linux should be more compact than Windows because of its standard modules. However, there is a lot of overload to shoulder the complexity of modern operating systems. A Linux root partition is typically over 250MB! As an exercise in how much functionality one can fit into 50MB, you should try (for fun) Damn Small Linux (DSL) which fits on a mini disc of 50MB and runs from a CD, using RAM as additional file space, and any USB pen drive to store permanent data on. It is also very fast.
• is Linux faster? Linux is not faster than Windows, generally equally fast and is at times noticeably slower why? Linux is portable to all present-day computers because it was written in a high-level language, with some kernel modules written in machine language for speed. Where it becomes noticeably slower is because many functions are programmed in 'script', which is a normal text file. For such text to execute, it must be interpreted letter by letter, and this can slow the process down 10-100 times compared to a compiled program. To my personal liking, there is just too much scripting in Linux, even where speed is important. Script is easy to debug and entirely portable between computer types.
• does Linux react faster? Where Linux excels is being predictable in reaction time. It reacts fast to interrupts, and because of this outperforms Windows in throughput, for instance in file servers and programs that work in real-time, like audio and video processes (and screen savers).
• does Linux performance degrade over time? Windows users know that Windows degrades over time, particularly where large files are used. For instance, during a heavy day of processing photographs, I may need to reboot Windows XP twice in order to regain performance. I had to have 2GB of RAM to get adequate performance. By contrast, Linux improves performance as the day proceeds, as its disk cacheing learns what you are using most. Furthermore, it does not degrade over time and does not need to be rebooted, not even after installing new software and drivers. It can run for weeks on end without giving any trouble.
• do Linux systems become messy over time? Windows users know that the C: drive becomes messy over time due to installing and uninstalling software. There is no reliable facility to clean up the mess in the registry, the volume information, temporary files and so on. Particularly Windows modules and service packs make it messy. However, this is similar with Linux, as no proper cleanup mechanism is available to get rid of temporary files and archives.
• do I get better support? customer support for Windows is abysmal apart from your first days at the computer, whereas Linux support fares much better. Distros for which you have paid, offer 'ticket systems' for urgent support, and aside from this, organise extensive user forums where users help one another. Even so, your best support comes from the people around you and there is plenty of work for IT consultants.
• how can I get an idea of a distro's level of support? Visit each distro's web site and see what levels of support they offer at what price. Then visit their support forums and mentally take note of the number of unresolved issues and the days it took to a satisfactory answer. Also look at the number of issues and their frequency.

For an extensive introduction to Linux, visit: http://www.ncsu.edu/it/mirror/ldp/intro-linux/html/intro-linux.html

The Xandros team is continually at work to update the database of approved packages, which by means of its Xandros Networks package installer, are a breeze to install. The installer also gives access to non-free and other packages, even those of the RPM stables.

Then Xandros focused on making the robust and fast Linux Apache web and enterprise server more user-friendly with a graphical user interface, which gives them a forward position in medium to large enterprises.

Xandros' philosophy is that of co-operating with the Windows world so that Xandros users won't be cut off from it. For this reason it actively supports and promotes CrossOver Office which makes the entire MS Office suite work in Linux, as well as other packages such as Photoshop. As the Windows Environment within Linux improves, more and more applications will run in Linux.

Already three years ago I wanted to migrate to Linux, and since then I have tried Xandros versions 1, 2, 3 and now 4. The improvements made during this time have been quite remarkable, to the extent that the switch to Xandros has become a major step forward.

Remember why we chose Xandros in preference to other distros? Because Xandros aims at Win-Lin interoperability, where Windows file system and files can live happily together with Linux file systems and files. Yet here is a bug that renders the whole exercise futile. One cannot accept for a moment that file date-time stamps are reset to today's when files are copied.

The Xandros File Manager (XFM) could be blamed for this, but the rot goes deeper. Even the copy command cp and the synchronisation function rsync fail in this respect. The manual says that the -t option (or --timestamp, --preserve=all) commands the date-time stamp to be preserved, but this does not work. So the rot may well be found much deeper. It also extends to ownership. Whereas in Windows 'personal' systems the user i.d. and ownership are not relevant, it is profoundly important in Linux. So what should the owner become when copying files from Windows to Linux? At the moment these files are given to root (Administrator) with full access privileges to others, but is this workable? One thing is sure: when copying from one Windows disk to another, the ownership should not change!

This serious bug has been reported to Xandros on 16 July 2007, so let's see how soon it is fixed. In the meantime, my advice to you is: don't move from Windows to Linux yet, because Linux is not ready. I have also had to give it a miss for now :(sob). However, when all you have is a Linux system, without any Windows files, Linux is quite ready for you!
 
 

2. Slow startup Linux is hailed as the compact operating system with speed, able to give your old PC a new life. Don't believe this immediately. One of its problems is related to bloatware and another to the extensive use of scripting. A script is an executable text file that is interpreted as it executes, letter by letter. It is very slow but easy to maintain and to debug.

The acid test is done by measuring the startup time of your computer. On an 1800MHz AMD Athlon, Xandros boots up in 144 seconds whereas WindowsXP does it in 104. Win98SE on a 600MHz Toshiba laptop boots up in 104s. Imagine it taking 7 minutes to boot up in Xandros on this laptop? A proper operating system should be able to wake up within four rings of a telephone, and neither Windows nor Xandros can achieve this.

Whereas Windows needs rebooting frequently, Linux distros can be left running. The only requirement is that they power down in a sleep or suspend state, or after writing memory to disk, when hibernating. However, with Xandros V4, none of these alternatives are working.
 
 

3. Slow Windows in Crossover or Wine Crossover is a Debian version of Wine. Wine provides the Windows environment in which Windows programs can run. Only Intel computers, for which Windows was designed, can run with Wine, as Wine is not an emulator of an Intel processor.

Thus Windows programs can run at their full speed, until they need services provided by the operating system, such as screen and disk acces, output to printers and so on. In Windows these functions are performed by Dynamically Linked Libraries (DLLs) and the Windows API interface. With quite a lot of effort, all these functions can be provided by Linux modules, but it would help considerably if Microsoft co-operated rather than obstructed these efforts. It would also help if these operating system functions were properly documented - they are not.

So, when a Windows program running under Wine requires to interact with peripheral devices, the result is uncertain. Yet quite a number of complicated Windows programs have been made to run in Wine, and more are sure to follow.
Where the user gets irritated, is when Windows programs open files by browsing disks and folders, which is agonisingly slow at the moment, likewise for saving files.

My suspicion is that this slow browsing is caused by inefficiently written code, or even by script. For professionals and businesses, who have to produce commercial throughput, this could well be an insurmountable stumbling block. This is clearly an area that needs attention of the Wine and CrossOver developers.