Operating Systems

Operating systems are obviously the basis of most computer software, but looking at the structure of an operating system is very helpful to understand other systems, like web servers or game servers, because they include lots of principles developed inside operating systems. Operating systems are now a commodity. Customers don?t want/need a veritable ?kitchen sink? Operating systems are not identical in terms of their graphical interface rendering capabilities or their support of data transfer and processing functions.

Operating systems are constantly being improved or upgraded as technology advances. When a company thinks that their operating system is now more advanced than the one already on the market, they release their new version for sale.

Windows is generally more popular when it is being used as a workstation (a regular desktop PC) and Linux is more popular as a server, more specifically a web server. Our main business at Intoweb revolves around web development. Windows, as many of you know, is not composable in this fashion; vendors do not have the ability to rip apart the operating system and include only the pieces they want. VMWare admitted as much, saying that Linux was far and away the predominant choice for the virtual appliances they have on hand currently. Windows offers multi-tasking, after a fashion, and a fairly useable interface, unless you happen to be used to a Mac. It even offers virtual memory: a real boon after DOS.

Windows is the clear leader, averaging 56% of the workload across all data centers. Trailing far behind is Unix at 17% and mainframe operating systems at 11%. Windows 2000 and Novell Netware can each support hundreds or thousands of networked users, but the operating systems themselves aren't true multi-user operating systems. The system administrator is the only "user" for Windows 2000 or Netware .

Is everything making sense so far? If not, I'm sure that with just a little more reading, all the facts will fall into place.
 
Applications running on personal computers have been taking advantage of the non-existing protection mechanisms in MS-DOS and the Apple Macintosh operating system to extend the operating system. For example, intercepting keystrokes and mouse events, as well as writing to screen memory directly is possible. Application (user) programs asked the operating system to perform various functions; users seldom talked to the OS directly.Today those boundaries are not quite so clear. The rise of graphical user interfaces, macro and scripting languages, suites of applications that can exchange information seamlessly, and the increased popularity of networks and distributed data--all of these factors have blurred the traditional distinctions.

UNIX was designed for many users sharing a computer system. All of these operating systems are in use at the Naval Postgraduate School. Unix/Linux operating systems are also a better choice when hosting multiple web sites with heavy bandwidth requirements and can provide a 99% or more uptime.

Linux was chosen primarily due to the wide range of hardware supported, the sophistication of its kernel and the availability of source code and documentation. We believe that ?hands-on? Linux and Mac operating systems are the two most commonly cited "secure" OSes. This idea is false and gives users of these systems a false sense of security. Linux seems to be the among the healthiest of the direct Unix derivatives, though there are  systems as well as the more official offerings from the workstation and mainframe manufacturers. I can't help observing, of course, thalso the various BSD e "free source" Unix-derived world seems to be suffering from exactly the same kind of fragmentation and strife that occurred and is still occurring in the commercial world.

Linux, in particular, comes in a huge variety of distributions; some act and look much like Windows; others can be used to build an appliance server (see below) that are totally administered through a Web or other interfaces. The core, or Kernel, of the operating systems are the same, however (although there may be variations in the version of the kernel used in a given distribution). Linux has succeeded as a product only because the community that supports it has organised itself systematically to create, share, test, reject, and develop ideas in a way that flouts conventional wisdom. Successful We-Think projects are based on five key principles that were all present in Linux.

Knowing enough about Operating Systems to make solid, informed choices cuts down on the fear factor. If you apply what you've just learned about Operating Systems, you should have nothing to worry about.