merge vs rebase in git

Git merge and git rebase are two different ways to integrate changes from one branch into another.

Git merge is used to combine multiple branches. When you merge one branch into another, you take the changes from the branch you want to merge and apply them onto the other branch. For example, suppose you have the following branches:

• master
• feature

If you want to merge the feature branch into master, you would run the following command:

git checkout master
git merge feature

This would apply the changes from the feature branch onto the master branch, creating a new commit that represents the merge. The resulting commit history would look something like this:

A - B - C (master)
         \
          D - E - F (feature)
               \
                G (merge commit)

Git rebase is used to apply the changes from one branch onto another, but instead of creating a new merge commit, it modifies the existing commits. For example, suppose you have the following branches:

• master
• feature

If you want to apply the changes from the feature branch onto the master branch using rebase, you would run the following command:

git checkout feature
git rebase master

This would apply the changes from the feature branch onto the master branch, modifying the existing commits in the feature branch to reflect the changes. The resulting commit history would look something like this:

A - B - C - D' - E' - F' (feature)
          \
           D - E - F (master)

Note that the commit IDs for the commits in the feature branch have changed, because the commits have been modified.

In general, git merge is a simpler and safer option for integrating changes from one branch into another. Git rebase is a more powerful option that can be useful in certain situations, but it can also be more complex and can cause problems if used improperly.