Note: don't forget to 'add' a file again if you modified it after the
first 'add' and before 'commit'. Otherwise only the previous added
state of that file will be committed. This is because git tracks
-content, so what you're really 'add'ing to the commit is the *content*
+content, so what you're really 'adding' to the commit is the *content*
of the file in the state it is in when you 'add' it.
2) By using 'git commit -a' directly
commits, they will be lost. Also, don't use "git reset" on a
publicly-visible branch that other developers pull from, as it will
force needless merges on other developers to clean up the history.
+If you need to undo changes that you have pushed, use gitlink:git-revert[1]
+instead.
The git grep command can search for strings in any version of your
project, so