Git is a distributed version control system. Git is free software distributed under the GPL. Git has a mutable index called stage. Git tracks changes. Creating a new branch is quick. Testing a new branch in dev branch and add and then commmit, then change to master, you will find they are different. Creating a new branch is quick and simple. Testing --no-of mode to git merge. Change in dev to test if sitll can merge. Add the bug branch.