What does M mean in Mercurial's hg status output

I'm using Mercurial and I开发者_StackOverflow中文版've modified a file in my local computer. hg status returns

M settings.py

But now I don't want to commit changes and I want to take back my file before last changes. How can I do it?

---

You can use hg update -C to update all tracked files to the working branch.

If you only want to revert a specific file use hg revert filename