GIT is a distributed version control system that allows to share codebase between developers. Born in Linux kernel world proved to be very useful for any programming task. "Distributed" means you can commit locally (during flight), syncing commits to some external repository is done in separate step (at the airport, waiting for luggage).
During watching my commit list using gitk I noticed many developers are accidentially merging their changes without so called "fast forward" (additional commit is created and the history is not linear). Why? The cause is that they are pulling changes from server AFTER local commit. A example commit tree taken from this worth-reading article:
The solution for this problem is to use "git pull –rebase" when downloading changes from repository. Existing local commits will be "rebased" (SHA-ids will change) and the history will be left linear. It looks much better:
"Rebasing" can be requested during pull by using this syntax:
git pull --rebase
I bet you will forget that after n-th commit 😉 That's why GIT allows to make rebase default option. Just do for every branch you have (including "master"):
git config branch.master.rebase true git config branch.branch_10.rebase true ...
And tell GIT to setup such rule for every new branch:
git config branch.autosetuprebase always
Of course you can disable automatic "rebasing" when needed:
git pull --no-rebase