"git pull" or "git merge" between master and development branches

This workflow works best for me:

git checkout -b develop

...make some changes...

...notice master has been updated...

...commit changes to develop...

git checkout master
git pull

...bring those changes back into develop...

git checkout develop
git rebase master

...make some more changes...

...commit them to develop...

...merge them into master...

git checkout master
git pull
git merge develop

Be careful with rebase. If you're sharing your develop branch with anybody, rebase can make a mess of things. Rebase is good only for your own local branches.

Rule of thumb, if you've pushed the branch to origin, don't use rebase. Instead, use merge.

The best approach for this sort of thing is probably git rebase. It allows you to pull changes from master into your development branch, but leave all of your development work "on top of" (later in the commit log) the stuff from master. When your new work is complete, the merge back to master is then very straightforward.