https://www.youtube.com/watch?v=P-EJ-Tkb5FM&list=PLuHgQVnccGMA8iwZwrGyNXCGy2LAAsTXk ================================================================================ git init vim f1.txt a git add f1.txt git commit -m "1" ================================================================================ vim f1.txt a b git add f1.txt git commit -m "2" ================================================================================ vim f1.txt a b c git add f1.txt git commit -m "3" ================================================================================ vim f1.txt a b c d git add f1.txt git commit -m "4" ================================================================================ git log ================================================================================ Go back to commit 3, and remove commit 4 git reset --hard 93c9 git log ================================================================================ ================================================================================ Cancel "reset which deleted commit 4" ================================================================================ ================================================================================ ================================================================================ git reset --hard ORIG_HEAD git log ================================================================================ git reflog ================================================================================ git log git checkout 93c9 git branch ================================================================================ ================================================================================ git checkout master