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Git is a distributed version control system.
Git is a free software distributed under the GPL.
are you fucking kidding serious?
2020.9.5 15:55  Git has a mutable index called stage.
9.6 ---> Git tracks changes of files.
9.8 ---> practice "git push -u origin master" from Git Bash.
9.8 --->在远程github仓库中修改。