A Red Hat® Package Manager file (rpm file) is a file or set of files used to install software on Linux® based systems. First introduced to support the Red Hat® distribution of Linux®, RPM has been included in many more distributions of Linux® and other Operating Systems like Novell Netware®.
The idea behind an rpm file is such that a group of files or an application can be packaged together and unpacked during the installation process. The technology is similar to compression used to package many word or excel documents together for distribution. Packaging installation files together reduces the size of the overall file and in turn the amount of time a user spends downloading and installing the rpm file.
The information about each package is stored in meta data, which is data that defines data to a computer. An rpm file, as it is unpacked, stores meta data in a database on the host computer which keeps information about the installed packages. This helps to maintain updates for applications and ensure that the host operating system knows which version of the installed package is most current.
Sometimes a front end application will be used to manage the RPM package files on a system. These applications are used to simplify the use of an RPM file even further by bringing them into the Graphical User Interface (GUI). Many distributions of Linux® are command line driven, leaving the user to enter the path to the application or RPM package files on the command line to make use of the package. The front end manager allows the user to download package files and then open them within the GUI environment, removing the command line from the equation.
RPM package files can also help new users to the Linux® arena become more familiar with the use of the operating system and make the setup process less daunting simply because it can be handled within the GUI desktop environment many users have become comfortable with.