As we mentioned earlier in section 1.1, the design of Debian
GNU/Linux comes from the Unix operating system. Unlike common
desktop operating systems such as DOS, Windows, and MacOS, GNU/Linux
is usually found on large servers and _multiuser_ systems.
This means that Debian has features those other operating systems
lack. It allows a large number of people to use the same computer at
once, as long as each user has his or her own _terminal_.[2] To
permit many users to work at once, Debian must allow many programs
and applications to run simultaneously. This feature is called
_multitasking_.
[2] A terminal is just a keyboard and a screen that are connected to
the computer through the network, over a modem, or directly. You
keyboard and monitor form a terminal that is directly attached to the
computer: This special terminal is often called the _console_.
Much of the power (and complexity) of GNU/Linux systems stems from
these two features. For example, the system must have a way to keep
users from accidentally deleting each other’s files. The operating
system also must coordinate the many programs running at once to
ensure that they don’t all use the same resource, such as a hard
drive, at the same time.
If you keep in mind what Debian was originally designed to do, many
aspects of it will make a lot more sense. You’ll learn to take
advantage of the power of these features.
1.3 What Is Free Software?
When Debian developers and users speak of “Free Software,” they
refer to _freedom_ rather than price. Debian is free in this sense:
You are free to modify and redistribute it and will always have
access to the source code for this purpose. The Debian Free Software
Guidelines[3] describe in more detail exactly what is meant by
“free.” The Free Software Foundation[4], originator of the GNU
Project, is another excellent source of information. You can find a
more detailed discussion of free software on the Debian web site[5].
One of the most well-known works in this field is Richard M.
Stallman’s essay, _Why Software Should Be Free_[6]; take a look at
it for some insight into why we support Free Software as we do.
Recently, some people have started calling Free Software “Open
Source Software”; the two terms are interchangable.
[3] http://www.debian.org/social_contract#guidelines
[4] http://www.fsf.org/
[5] http://www.debian.org/
[6] http://www.fsf.org/philosophy/shouldbefree.html
You may wonder why would people spend hours of their own time
writing software and carefully packaging it, only to give it all
away. The answers are as varied as the people who contribute.
Many believe in sharing information and having the freedom to
cooperate with one another, and they feel that free software
encourages this. A long tradition that upholds these values,
sometimes called the Hacker[7] Ethic, started in the 1950s. The
Debian GNU/Linux Project was founded based on these Free Software
ethics of freedom, sharing, and cooperation.
[7] Note that the term “hacker” should not be confused with the term
“cracker.” In short, a hacker is benevolent, whereas a cracker is
generally considered malevolent. Movies and other forms of media many
times incorrectly use the term “hacker” instead of “cracker.”
Others want to learn more about computers. More and more people are
looking for ways to avoid the inflated price of proprietary
software. A growing community contributes in appreciation for all
the great free software they’ve received from others.
Many in academia create free software to help get the results of
their research into wider use. Businesses help maintain free
software so they can have a say in how it develops—there’s no
quicker way to get a new feature than to implement it yourself or
hire a consultant to do so! Business is also interested in greater
reliability and the ability to choose between support vendors.
Still others see free software as a social good, democratizing
access to information and preventing excessive centralization of the
world’s information infrastructure. Of course, a lot of us just find
it great fun.
Debian is so committed to free software that we thought it would be
useful if it was formalized in a document of some sort. Our Social
Contract[8] promises that Debian will always be 100% free software.
When you install a package from the Debian main distribution, you
can be sure it meets our Free Software Guidelines.
[8] http://www.debian.org/social_contract
Although Debian believes in free software, there are cases where
people want to put proprietary software on their machine. Whenever
possible Debian will support this; though proprietary software is
not included in the main distribution, it is sometimes available on
the FTP site in the non-free directory, and there is a growing
number of packages whose sole job is to install proprietary software
we are not allowed to distribute ourselves.
It is important to distinguish _commercial_ software from
_proprietary_ software. Proprietary software is non-free software;
commercial software is software sold for money. Debian permits
commercial software, but not proprietary software, to be a part of
the main distribution. Remember that the phrase “free software” does
not refer to price; it is quite possible to sell free software. For
more clarification of the terminology, see
http://www.opensource.org/or
http://www.fsf.org/philosophy/categories.html.