1.4 Distribution

1.4.1 Birth of distribution

As mentioned above, Linux was referring to the kernel part. Moreover, using the tools that GNU and so on offered, various programs such as the commands are gathered, then it has come to function as UNIX.. However, only the users with high skill were able to use Linux because operation until use, that was the installation, was very difficult. Therefore, collecting necessary programs, making an easy installer were made, so that users who do not have high skills can easily install it. It is called the distribution.
Organizations offering distribution have various policies. There are organizations trying to thoroughly check the quality and to provide a stable program group with few troubles even if it is somewhat old. Other organizations are trying to provide the latest program group as much as possible. And there are other organizations that change some parts of existing distribution, adding some packages, and provide it as their own original distribution.
Examples of distribution: Red Hat Enterprise Linux, Debian GNU / Linux

1.4.2 Package

In talking about the distribution, there is the package as a necessary mechanism. As mentioned above, you need to install various programs to start using Linux. Without packages, besides the difficulty of installation, there are the following problems.

Complex programs require multiple dependent programs. If dependent programs are dependent on yet another program, they must be installed in the correct place in the correct order.

Programs to develop actively always has the update. When installing a new program, delete the old program that is currently running cleanly and install it. Deleting program is also as difficult as installing program.

The package is used to solve these difficult problems. The package manages the installed file and the version of the program. Moreover, when the package is installed, the dependent package is also installed automatically because the dependency of the program is managed. There is a company named RedHat as a distribution to contribute to the management of the package greatly. RedHat developed the mechanism named RPM(RedHat Packaging Manager) for its own distribution. It is general to use this PRM for the package management now. In a part of distributions, the package management of the DEB form might be used. It will be able to be said that RPM is 90% or more if it says in the ratio. This installed and running environment, including the packaged distribution, may be called Linux. This is a broad meaning of Linux.