Git diff single file between branches

Developers often wish to compare files between Git branches, particularly with a GUI like Meld. Setup Meld with Git like:

git config --global diff.tool meld
git config --global merge.tool meld

All files different between the current Git branch to another Git branch “develop” are revealed like:

git difftool develop

Compare a single file to another Git branch “develop”:

git difftool develop -- src/myfile.c