GMan 2 is an alternative of Gman software, because it's outdated ( dating back to 1999 ) and not very functional today. As its predecessor, it's a graphic front-end to view linux manpages.
The functionalities as the same of Gman except for the browser to open the manpages, it can be changed setting the favorite browser inside an environment variable BROWSER, if this variable was not set, GMan 2 use one of this browser: firefox, konqueror, opera, iceweasel or epiphany-browser.
The paths where manpages are located can be added manually in the graphic interface, or searched automatically. If you want save these paths permanently will be created the file .gman_2.paths in your home folder.