Competing Operating Systems
Tharindu Weerasinghe - Computer Engineer
Last week we spoke of various characteristics of Operating Systems.
Now we analyse compare some example of operating systems.
Microsoft Windows
 Microsoft Windows is a family of proprietary operating systems. It is
by far the most common family of operating systems for the personal
computer, taking in over 90 percent of the market share. Currently, the
most widely used version of the Microsoft Windows family is Windows XP,
released on October 25, 2001. The newest version is Windows 7 for
personal computers and Windows Server 2008 for servers.
It originated in 1981 as an add-on to the older MS-DOS operating
system for the IBM PC. Released in 1985, Microsoft came to dominate the
business world of personal computers, and went on to set a number of
industry standards and commonplace applications.
Windows is also used on servers, supporting applications such as web
servers and database servers. In recent years, Microsoft has spent
significant marketing and research and development money to demonstrate
that Windows is capable of running any enterprise application, which has
resulted in consistent price-performance records and significant
acceptance in the enterprise market. However, its usage in servers is
not as widespread as personal computers, and here Windows actively
competes against Linux and BSD for market share, while still capturing a
steady majority by some accounts.
Linux and GNU
Linux is a generic name for a member in a family of operating systems
that can be found on anything from supercomputers to wristwatches.
Because its components are open source, anyone can read and modify its
code. Consequently it has been modified for a huge variety of
electronics. It is used on only 0.5 to two percent of all personal
computers, but it is a silent giant in the world of cell phones,
servers, and embedded systems. It is used on the 10 most powerful
supercomputers in the world.
The GNU project is a mass collaboration of programmers who seek to
create a completely free and open operating system that was similar to
UNIX but with completely original code. It was started in 1983 by
Richard Stallman, and is responsible for many of the parts of most Linux
variants. For this reason, Linux is often called GNU/Linux.
 Meanwhile, the Linux kernel began as a side project of Linus Torvalds,
a university student from Finland. In 1991, Torvalds began work on it,
and posted information about his project on a newsgroup for computer
students and programmers. He received a wave of support and volunteers
who ended up creating a full-fledged kernel. Programmers from GNU took
notice, and members of both projects worked to integrate the finished
GNU parts into the linux kernel in order to create a full-fledged
operating system.
UNIX and Unix-like operating systems
UNIX was written by Ken Thompson based on BCPL. UNIX developed into a
large, complex family of interrelated operating systems which have been
influential in every modern operating. The Unix-like family is a diverse
group of operating systems, with several major sub-categories including
System V, BSD, and GNU/Linux.
Unix-like systems run on a wide variety of machine architectures.
They are used heavily for servers in business, as well as workstations
in academic and engineering environments. Free UNIX variants, such as
GNU/Linux and BSD, are popular in these areas. Some UNIX variants like
HP’s HP-UX and IBM’s AIX are designed to run only on that vendor’s
hardware. Others, such as Solaris, can run on multiple types of
hardware, including x86 servers and PCs. Apple’s Mac OS X, a hybrid
kernel-based BSD variant derived from NeXTSTEP, Mach, and FreeBSD, has
replaced Apple’s earlier (non-Unix) Mac OS.
BSD and its descendants
A subgroup of the UNIX family is the Berkeley Software Distribution
family, which includes FreeBSD, NetBSD, and OpenBSD. These operating
systems are most commonly found on web servers, although they can also
function as a personal computer OS.
The internet owes much of its existence to BSD, as many of the
protocols now commonly used by computers to connect, send and receive
data over a network were widely implemented and refined in BSD. The
World Wide Web was also first demonstrated on a number of computers
running an OS based on BSD called NeXTSTEP.
BSD has its roots in UNIX. In 1974, University of California,
Berkeley installed its first UNIX system.
Over time, students and staff in the computer science department
there began adding new programs to make things easier, such as text
editors. When Berkely received new VAX computers in 1978 with UNIX
installed, the school’s undergraduates modified UNIX even more in order
to take advantage of the computer’s hardware possibilities.
The Defense Advanced Research Projects Agency of the US Department of
Defense took interest, and decided to fund the project. Many schools,
corporations, and government organizations took notice and started to
use Berkeley’s version of UNIX instead of the official one distributed
by AT&T.
Steve Jobs, upon leaving Apple Inc. in 1985, formed NeXT Inc., a
company that manufactured high-end computers running on a variation of
BSD called NeXTSTEP. One of these computers was used by Tim Berners-Lee
as the first web server to create the World Wide Web.
Mac OS X
Mac OS X is a line of partially proprietary, graphical operating
systems developed, marketed, and sold by Apple Inc., the latest of which
is pre-loaded on all currently shipping Macintosh computers. Mac OS X is
the successor to the original Mac OS, which had been Apple’s primary
operating system since 1984.
The operating system was first released in 1999 as Mac OS X Server
1.0, with a desktop-oriented version (Mac OS X v10.0) following in March
2001.
Since then, six more distinct ‘client’ and ‘server’ editions of Mac
OS X have been released, the most recent being Mac OS X v10.6, which was
first made available on August 28, 2009. Releases of Mac OS X are named
after big cats; the current version of Mac OS X is nicknamed ‘Snow
Leopard’. |
