One of Git's core value-adds is the ability to edit history. Unlike version control systems that treat the history as a sacred record, in git we can change history to suit our needs. This gives us a lot of powerful tools and allows us to curate a good commit history in the same way we use refactoring to uphold good software design practices. These tools can be a little bit intimidating to the novice or even intermediate git user, but this guide will help to demystify the powerful git-rebase.
This document is an attempt to be a fairly comprehensive guide to recovering from what you did not mean to do when using git. It isn't that git is so complicated that you need a large document to take care of your particular problem, it is more that the set of things that you might have done is so large that different techniques are needed depending on exactly what you have done and what you want to have happen.