Using Git

Removing/undoing your changes to a file

 git checkout -- <path>

If "path" is ".", you undo all your changes to version controlled files:

 git checkout -- .

Note: if you've first done git add (to "stage your changes", so some file is listed under Changes to be committed), you first need to do git reset to unstage the changes, then checkout:

git reset HEAD .
git checkout -- .

Merge conflict: Throw away local changes

 git checkout master <path>
 git commit
 git merge master

(The last command should now do nothing, just say you're fully merged.)