Man Pages

Man pages is the short form of manual pages, and the term is used for talking about online software documentation that’s normally included in the UNIX-like and/or UNIX operating systems. The topics covered in man pages include the details related to the computer programs (including system calls and library), formal standards and even abstract concepts.

The users can invoke a call for the man pages by employing the ‘man’ command. The ‘man’ command normally uses a terminal pager program, for instance ‘less’ or ‘more’ for displaying its output. You can read about any UNIX command by fetching its manual page. This can be achieved by typing in
man < command_name >

Now, coming to the history of manual pages, none existed during the initial two years of UNIX. The Unix Programmer’s Manual got published for the first time on November 3, 1971. Apart from the manual pages, this Programmer’s manual also had very short papers, some of them being tutorials related to C programming language, general UNIX usage and usage of tools like Yacc, as well as detailed descriptions related to the operating system’s features. The manual was so comprehensive that its print version could easily fit into a single binder. It further expanded with the passage of time and introduction of advanced UNIX versions. As of Research Unix 7th Edition, the manual was split into two volumes, the print version of the man pages constituted volume 1.

Man pages are normally written in English language, but there are translations available in other languages too. The default format used the publishing of man pages referred to as ‘troff’, which is either semantic oriented (mdoc) or appearance oriented (macro package man). It facilitates easy typesetting of the man pages into PDF, PostScript and several other formats for easy printing and/or viewing. Majority of UNIX systems comprise of a package for man2html command whose execution enables the users to browse through the man pages inside an HTML browser.

About their layout
The man pages usually follow a common layout format which is optimized for proper presentation on basic ASCII text display, without the need of any font control or highlighting. The sections included may be something like:
Name - The name of the function or command, followed by its one line description.
Synopsis – If it’s a command, a formal description related to its running and the options it takes. In case of a program function, the parameters it takes.
Description – A text-based description related to the function or command’s functioning.
Examples – Common usage examples
See also – Some related functions or commands

Coming to the Tcl Tk man pages, they’re all normally included in the distributions of software created with Tcl Tk. Their copies are also maintained online.