how to revert a a git project back to the master code example

Example 1: git how to roll back to a commit

//git use a new commit to replace an old commit,commit moves foward not backward
git revert <commit hash>
//Git goes back one spot on the log,undone this commit and go backward one commit:
git reset HEAD~1
//Git looks for and rolls back to a certain file:
git checkout commit-hash-here -- file/location/and/name

Example 2: how to revert a git revert

git revert <commitHashOfTheRevert> # locate the hash the revert was done 
                             #this will invert the changes made in that commit
                             #and preserve the git history