Package meld

Visual diff and merge tool

http://meldmerge.org/

Meld is a visual diff and merge tool targeted at developers. It helps you
compare files, directories, and version controlled projects. It provides two-
and three-way comparison of both files and directories, and the tabbed interface
allows you to open many diffs at once.
Meld has has support for many popular version control systems including Git,
Mercurial, Bazaar, SVN and CVS. The diff viewer lets you edit files in place
(diffs update dynamically), and a middle column shows detailed changes and
allows merges. The margins show location of changes for easy navigation.
General Commands (Section 1)
meld
Meld is a graphical diff viewer and merge application for the GNOME desktop. It supports 2 and 3-file diffs, recursive directory diffs, diffing of directories...