Merge a branch in Git

Branches are Git's way to organize separate lines of development, allowing a team to work multiple features in parallel. But at some point, you'll want to merge a branch into another branch, usually master or main. Depending on your team's workflow, merging a branch might create a merge commit or not.
In order to merge a branch, you want to switch to the target branch first, using git checkout. Then, you can use git merge to merge the source branch into the target branch.
By default, Git will use fast-forward merge to merge the branch. This means that it will create a linear history, by placing the commits from the source branch at the tip of the target branch.
If, instead, you want to create a merge commit, you can use the --no-ff flag when merging. This will create a merge commit at the tip of the target branch, optionally referencing the source branch in the commit message. The rest of the process remains the same.

# Syntax:
#  git checkout <target-branch>
#  git merge <source-branch>

git checkout master
git merge patch-1 # Merges the `patch-1` branch into `master`

By default, Git will use fast-forward merge to merge the branch. This means that it will create a linear history, by placing the commits from the source branch at the tip of the target branch.
If, instead, you want to create a merge commit, you can use the --no-ff flag when merging. This will create a merge commit at the tip of the target branch, optionally referencing the source branch in the commit message. The rest of the process remains the same.

From 30-seconds-of-code: merge-branch-merge-commit