Editing Rn (newsreader) (section)

==Features==
''rn'' was also notable for three other features it introduced: [[Kill file]], "do the right thing", and automatic configuration. 

A Kill file is a [[computer file|file]] (called, obviously enough, {{mono|KILL}}) containing [[regular expressions]] matched against the subjects of news articles in each group. If an article matches, it is marked as having already been read. This feature was essential as the growth of the Usenet made it impossible to read every article in even a limited selection of newsgroups.

"Do the right thing" introduced a fundamental change in [[user-interface]] from previous news software. Rather than require a user to navigate menus or learn a command vocabulary for each mode of the program, certain single-keystroke commands were used throughout the user interface to perform the most appropriate function based on context. For example, the space character will "go on to the next thing", and the ''next thing'' could be the next page, the next article, or the next newsgroup, depending on where the user is in the process of reading news.

Finally, automatic configuration is a feature for [[system administrator]]s {{endash}} not visible to [[end user|users]] {{endash}} that allows for [[software build|building]] and [[Installation (computer programs)|installing]] the application with relative ease. Most Unix programs, and in particular Usenet software, were (and still often are) distributed in [[source code]] form which requires building and installing before users can use it. Because different versions of Unix were organized differently, a system administrator required sufficient programming skill to modify the source code to account for these differences. ''rn'' changed that paradigm by including a script, called ''Configure'', with enough intelligence to customize the build and install process for the system it was running on. Since its introduction in the ''rn'' [[codebase]], the pattern of including a similar [[configure script]] in any [[software distribution]] became and still is popular.