A quick note on how to set up GUI difftool to use with git on Windows (Git Bash, Cygwin, etc…).

Download and install GUI diff tool of your choice, get the path to executable.

Create difftool.sh in directory included in your path (for example C:\Users\{username}\bin in Git Bash). Let’s take SourceGear’s DiffMerge as an example.

"C:/Program Files/SourceGear/Common/DiffMerge/sgdm.exe" "$1" "$2" | cat

And in your ~/.gitconfig:

    tool = diffmerge
[difftool "diffmerge"]
    difftool.sh "$LOCAL" "$REMOTE"

And difftool is available via git difftool command now.