The Most Popular Operating Systems(转)

AIX (Advanced Interactive eXecutive) - a proprietary (i.e., commercial) flavor (i.e., variant) of UNIX launched by IBM in 1990 for use on its mainframe computers.

Amiga - launched with the

pioneering Amiga personal computer in 1985 and continues to be

developed today for the PowerPC processor. Amiga features an elegant GUI (graphical user interface) together with some of the flexibility of Unix-like operating systems.

BeOS - developed by Be Incorporated in 1990 as a media operating system
that was optimized for digital media (e.g., digital audio, digital

video and three-dimensional graphics). BeOS has some Unix-like

characteristics, including its use of the bash (the default on Linux) command shell
and its directory structure, but it was written in entirely new code.

The loyal user base was very disappointed when the company failed

commercially, and thus several open source projects, including, are under way that are aimed at recreating and updating (e.g., new video drivers) BeOS.

Darwin - an open source derivative of 4.4BSD1 (Berkeley Software Distribution Version 4.4) that serves as the core for the Macintosh OS X. It was originally released in March 1999. There is also a GNU version of Darwin, which is called GNU-Darwin.

FreeBSD - the most popular of

the BSD operating systems, accounting for approximately 80 percent of

BSD installations (at least until Darwin came onto the scene). FreeBSD

was begun in early 1993 based on 4.3BSD, and the first version, 1.0,

was released in December of that year.

FreeDOS - begun in 1994 by Jim Hall with the goal of becoming a complete, free and fully MS-DOS compatible operating system for x86 (i.e., Intel-compatible) CPUs (i.e., central processing units).

GNU/Hurd -

has been under development by Richard Stallman and his Free Software

Foundation (FSF) since 1990. The core component, the Hurd (Hird of Unix-replacing daemons) kernel
(i.e., the core of the operating system), is still not completed

because of its very ambitious goal: to surpass Unix-like kernels in

functionality, security and stability while remaining largely

compatible with them.

- a proprietary flavor of UNIX developed by Hewlett-Packard for its HP

9000 series of business servers. HP-UX 1.0 was released in 1986.

IRIX - a

proprietary flavor of UNIX introduced by Silicon Graphics, Incorporated

(SGI) in 1982 for applications that use three dimensional visualization

and virtual reality.

JavaOS - developed by Sun Microsystems in 1996 for use in embedded systems (i.e., combinations of circuitry and software built into other products). JavaOS is written primarily in the Java programming language and includes a Java virtual machine (which allows running of any Java program regardless of the type of CPU used) as a fundamental component.

Linux - a high performance, yet completely free, Unix-like operating system launched by Linus Torvalds in 1991. GNU/Linux,

as it is also called (because it makes extensive use of utilities and

other software developed by the GNU project) is suitable for use on a

wide range of platforms and is compatible with both 32 bit and 64 bit processors. More than 200 distributions
(i.e., versions) of Linux have been introduced, among the most popular

of which are Red Hat, SuSE, Mandrake, Debian and Ubuntu. Although its

overall market share is still small, Linux is the most rapidly growing

of any major operating system.

Mac OS X - was released

by Apple Computer, Inc. in 2001 as a replacement for its aging Mac OS

operating system. Now commonly referred to as Mac Classic, the

pioneering Mac OS was introduced with the first Macintosh computers in

1984, and it was the first commercial operating system to include a

GUI. Mac OS X was developed as an entirely new, BSD-based operating

system that runs on a more advanced processor (the PowerPC) but which

maintains backward compatibility with the Mac OS (which runs on the

Motorola m68k). The Mac OS X consists of Darwin and the Mach microkernel (an advanced kernel developed at Carnegie-Mellon University) together with Apple’s proprietary Aqua
GUI (which is widely regarded as the best in the industry). Apple is

currently completing a transition of its hardware and OS X from the

PowerPC to x86 processors.

Microsoft Windows - the

successors to the very popular MS-DOS, it was announced in 1983, and

the first version, Windows 1.0, was finally released in 1985. Microsoft

Windows encompasses two groups of operating systems (i.e., Windows

95/98/ME/CE and Windows NT/2000/XP) which resemble each other

superficially and share compatibility with many of the same application

programs but which have very different internal structures.

MINIX - a small, open source UNIX clone that was first released in January 1987. It was written for use in computer science
education by Professor Andrew S. Tanenbaum of Vrije Universiteit in

Amsterdam, and it is now best known for its role in inspiring Linus

Torvalds to develop Linux.

MS-DOS - a single-user, single-tasking operating system that uses a command line (i.e., text only) user interface.

It was launched by Microsoft in 1981 and used on the first personal

computers, which were introduced by IBM in the same year. In spite of

its very small size and relative simplicity, MS-DOS is one of the most

successful operating systems that has been developed to date.

NetBSD - a derivative of 4.3BSD and launched in 1993, as was the case with FreeBSD. It is possibly the most portable of all operating systems, with the ability to run on more than 50 processors, ranging from the acorn26 to the x86.

OpenBSD - spun off from NetBSD

in 1996 by Theo de Raadt in Calgary, Alberta because of a desire to

place even more emphasis on security. OpenBSD has a goal of becoming

the most secure operating system, and it claims to have had only one

remote hole in the default install in more than eight years.

Palm OS - developed by

PalmSource, Inc. for personal digital assistants (PDAs). Palm OS

features flexibility and ease of use. It is the leading PDA operating

system, used in more than 36 million mobile devices, and there are more

than 20,000 software titles for it, far more than for any other

handheld platform.

QNX - a Unix-like, POSIX-compliant2, real time
operating system developed in 1982 that is widely used for mission- and

life-critical embedded applications. QNX can also be used as a desktop

operating system and features a unique and attractive GUI. Although it

is a commercial operating system owned by QNX Software Systems in

Ontario, Canada, it is free for personal use.

SkyOS - a commercial hobbyist

operating system developed by Robert Szeleney from 1996. SkyOS has some

features that resemble BeOS. It is mostly POSIX compliant, and comes

with many of the GNU utilities, including the very highly rated GCC (GNU Compiler Collection).

Solaris - developed by

Sun Microsystems for its SPARC processor and the most widely used

proprietary flavor of UNIX. Solaris was introduced as SunOS in 1989,

and it was based on BSD Unix. A version for x86 processors is also


TRON (The Real-time

Operating system Nucleus) - started by Professor Ken Sakamura of the

University of Tokyo in 1984 with the goal of creating an ideal computer architecture.

TRON claims to be the world’s most widely used operating system because

it is embedded in a vast number and variety of electronic products. The

TRON specifications are open, but there is no requirement to make source code (i.e., the human-readable form in which the software is originally written) freely available, in contrast to the GPL3.

Tru64 - a proprietary

flavor of UNIX offered by Hewlett-Packard for the 64-bit Alpha

processor. It is unusual among Unix-like operating systems in that it

is built on the Mach kernel, which is also used in Mac OS X. Tru64 was

originally developed by Digital Equipment Corporation (DEC) and called

Digital UNIX.


1BSD (Berkeley Software Distribution)

is a version of UNIX that was developed at the University of California

at Berkeley (UCB) in the 1970s. It is the ancestor of the modern BSDs

(i.e., FreeBSD, NetBSD, OpenBSD and Darwin) and its technology was also

incorporated into the other Unix-like operating systems as well as into

other operating systems, including Microsoft Windows. The final version

was 4.4BSD.

2POSIX (Portable Operating System Interface for uniX) is a set of programming interface standards
governing how to write source code so that the applications are

portable between operating systems. POSIX support was at one time

adopted by the U.S. government as a standard requirement for its

purchases. Linux and other Unix-like operating systems are POSIX


3The GPL (GNU General Public License), the most popular of the many free software
licenses, requires that the source code of any GPL-licensed work, or of

any work based on a GPL-licensed work, be made freely available.