Linux Library: A Dictionary of Open Source Terms

Apache
Apache, an Open Source product born in 1995, is the product of a series of patches, or "fixes" to the HTTP demon. It is a play on words for "a patchy server." It represents 54.65 percent of the Web server market (compared with Microsoft NT's 23.58 percent). (See wysiwyg://16/http://www.cnn.com/TECH/computing/9903/24/mslinux.html/index.html)

BSD License
This license is vastly different from the GPL. First used for the Berkeley Software Distribution of Unix, it allows one to modify the source code to the Unix operating system, compile it and own it. As was seen from the use of the BSD license, each commercial variant fragmented Unix as an industry and paved the way for Microsoft's Windows NT.

Closed Source
Closed Source software refers to software that source code does not accompany. Usually commercial in nature, closed source software also includes freeware and shareware software. In addition to its lack of source code, it is characterized by unknown bugs, inability to customize, and usually higher prices than Open Source software.

Copyleft
Copyleft is a term coined by Richard Stallman, founder of the Free Software Foundation, that in a wry sort of way, defines the function of the General Public License (GNU): Namely, that software is "protected" in its public use. As one writer noted, Stallman "first copyrights it, thereby preventing someone else from seizing control of it at a later date, then gives it away under controlled conditions that are essentially protected by Contract Law."

Exchange Culture
An "exchange culture" is one where software is owned and restricted. It is the opposite of the "gift economy" in which Open Source would best thrive. It is a term used by Eric Raymond, one of the founders of the Open Source Initiative, in his "Homesteading the Noosphere."

Forking
Forking is what happens in software product development when the child product becomes incompatible with the parent. Detractors of Open Source look to Unix as the prime example of forking. The difference between what happened to Unix and what might happen to Linux is the General Public License. Explains Eric Raymond: "It's really a red herring. Forking into incompatible versions is mainly a problem where you have a whole bunch of closed products that are supposedly working from the same open standard, but, in fact, the companies are frantically trying to differentiate to gain a competitive advantage.

"In the Linux world, the situation is completely different. Everybody's operating off the same open-source base, which means you can't differentiate the code for commercial advantages. As soon as you make a change, it goes back into common pool, and everybody gets to use it. That means you have to differentiate off of service, which is good for consumers. It also means that there's no tendency for the code base to fly apart. There's no significant tendency to fork because there's no advantage in forking. In fact, the licenses require that changes that one party makes be made available to everybody."

(http://www.businessweek.com/bwdaily/dnflash/apr1999/nf90427c.htmfork)

Free Software
Not to be confused with shareware or freeware, Free Software is software protected by the GNU GPL and the Free Software Foundation. Eric Raymond is reluctant to use the term "free software." He said, "after the Netscape announcement broke in February 1998, I did a lot of thinking about the next phase--the serious push to get 'free software' accepted in the mainstream corporate world. And I realized we had a serious problem with the term 'free software' itself. I've become convinced that the term has to go."

(http://www.tuxedo.org/%7Eesr/open-source.html)

Freeware
Freeware is software that is placed in the public domain without attachments, legal or moral. Users may utilize the programs in any manner possible, but the use to which they are put is severely limited because these programs do not include source code.

Gift Economy
The economic model by which Eric Raymond advocates Open Source software. Programmers and others give software to the community. The only restriction is that it cannot be "owned" by anyone. A gift economy is the opposite of the "exchange culture." Larry Wall, the creator of Perl scripting language, perhaps explained the gift economy best. He said, "I come from a culture where you're valued not so much by what you acquire but by what you give away."

GNU
An acronym meaning "Gnu's Not Unix", coined by Richard Stallman to describe the movement to replace Unix with GPL'd software.

GNU/Linux
Properly stated, according to Stallman, the Linux operating system comprises the Linux kernel and GNU utilities. Linux should, therefore, be named "GNU/Linux," according to Stallman.

GPL
GPL refers to Richard Stallman's GNU General Public License, under which software is "copylefted."

Hurd
Hurd is the name of the kernel development by the Free Software Foundation. When completed, it would compete directly with Linux.

Linux
The Linux operating system kernel is perhaps the most widely known example of Open Source software. Begun as a doctoral dissertation project at Helsinki [Finland] University by Linus Torvalds, Linux stands for "Linux Isn't Unix." Linux is not, as Stallman says, the entire operating system. Much of what is in commercial and public distributions of Linux are GNU and other utilities, "packages" in Linux parlance.

Linux Standard Base
The mission of Linux Standard Base, as taken from its Web site (http://www.linuxbase.org/), is that "the goal of the Linux Standard Base (LSB) is to develop and promote a set of standards that will increase compatibility among Linux distributions and enable software applications to run on any compliant Linux system. In addition, the LSB will help coordinate efforts to recruit software vendors to port and write products for Linux."

Open Source Definition
Eric Raymond explained, "The Open Source definition is derived from the Debian Free Software Guidelines. Bruce Perens composed the original draft; it was refined using suggestions of the Debian GNU/Linux Distribution developers in e-mail conference during most of June 1997. They then voted to approve it as Debian's publicly stated policy. It was revised somewhat and Debian-specific references were removed at the origination of the Open Source Program in February 1998." (http://www.opensource.org/history.html)

Open Source Software
Open Source is a software development and distribution methodology. Open Source software is characterized by several conditions:
The source code must be made available
All have the right to freely modify the source code
Any modifications to the source code must also be free
No price can be affixed beyond the reasonable cost to reproduce the software.

Open Source Initiative
The Open Source Initiative was established by Open Source advocates Bruce Perens and Eric Raymond as a "watchdog" organization. "The Open Source Initiative is dedicated to managing and promoting the Open Source Definition for the good of the community, specifically through the OSI Certified Open Software certification mark and program." (http://www.opensource.org/)

Open Source Licenses
Open Source Definition and the GPL are not the only expressions of "free" software licensing schemes. Other examples include:
* Netscape and Mozilla Public Licenses (http://www.mozilla.org/NPL/)
* Sun's Community Software License(http://java.sun.com/features/1998/12/source_license_QA.html)
*Apache License. (http://www.apache.org/LICENSE.txt.)
* Caldera Systems' license is a combination of Open Source for what it terms the "non-commercial" packages it includes. Its license also includes:
* additional licensing for the third-party commercial software packages that it bundles. Reports BusinessWeek Online, "Commercial Linux provider Caldera Systems ships products that carry three different licensing schemes, two of which grant some extra rights to software authors."

Peer Review
Peer Review is the process by which peers of Open Source software are able to review the source code, make recommendations and changes to the code. The result of peer review is reliability. Examples of highly reliable software used on the Internet are Perl, sendmail, Apache and Bind.

Shareware
Shareware is commercial software. Pioneered by Jim Button, shareware is either fully functioning or is crippled in features, employs "nag screens" that discourage use beyond a certain period, or has some date-enabled time bomb that makes the software unusable. The defining feature of shareware is the method of distribution and purchase. Shareware is usually distributed via the Internet. Payment is made directly to the author via check, cash or credit card after receipt of which an unlock key is sent to the purchaser that removes any limitations on use. There are third-party companies that offer to shareware authors credit card transaction clearance that facilitates the use of E-cash. Usually the same licenses that accompany any other commercial software, along with the identical limitations, are passed on to the customer. No source code is available with shareware software.