"Since its inception, the Xfce desktop environment has aimed to
provide high functionality with only modest demands on system
resources, with the overarching goal of leaving more facilities for
the user to run applications. One of the significant changes in
recent releases of Xfce 4 is the Thunar file manager, which
replaces the original xffm. Thunar does a good deal to advance the
goals of its parent project: it's fast and lean, especially by
today's standards of hardware, yet it offers rich functionality.
Like its namesake, Thunor, the Saxon god of thunder, Thunar is much
smaller than ;giants' like Konqueror and Nautilus, yet powerful in
its own right. If you want some of the functionality afforded by
the GUI file managers of the larger desktop environments, but with
less overhead, Thunar may fit your needs.
"Getting Thunar is fairly trivial, given that most recent
distributions package Xfce 4. Once you have it, you can start it
from within Xfce from the desktop or panel launchers, or from
outside of Xfce by running the command Thunar--an exception to the
Unix lower-case convention..."