One thing that cannot be undone
-------------------------------
-"Commit early, commit often".
+Whatever you undo, there is one thing that cannot be undone -
+overwritten uncommitted changes. Uncommitted changes don't belong to
+git so git cannot help with them - no way.
+
+Most of the time git warns you when you're going to execute a command
+that overwrites uncommitted changes. Git warns you when you try to
+switch branches with ``git checkout``. It warns you when you're going
+to rebase with non-clean working tree. It refuses to pull commits over
+non-committed files.
+
+But there are commands that designed exactly for that - overwriting
+files in the working tree. With commands like ``git checkout $PATHs``
+or ``git reset --hard`` git silently overwrites files including your
+uncommitted changes.
+
+With that in mind you can understand the stance "commit early, commit
+often". Commit as often as possible. Commit on every save in your
+editor or IDE. You can edit your commits before pushing - change,
+reorder, combine. But save your changes in git database, either in
+commits or at least in stashes.
Merge or rebase?