Some time ago I created branch from development branch and actually I did nothing with it, just one commit editing comment.
Now I want to start to work with this branch, but I want to update it with commits from development.
Actually I can just drop it and create branch again, but I'm interested what happened if I do merge or rebase with development.
Because this branch practically without commits, I suppose that there is no difference between merge and rebase. Am I right?
And what happened if I do in other direction first: merge development branch with this branch first?
There is a difference between a rebase and a merge, which will manifest (solely) in your commit history graph.
Rebase:
If you do a rebase, your commit history will look like you used your main branch to create your development branch and your one development commit today. (The timestamps will of course tell a different story). Your commit history will be linear.
All rebase conflict resolutions will be placed in this development commit.
Merge:
If you do a merge, git will create a merge commit that combines your main branch and your development branch. This merge commit will have two parents - the head (or tip) of your main branch and the head (or tip) of your development branch. Your commit history will not be linear.
All merge conflict resolutions will be placed in this merge commit.
Direction of merges
A merge in git does not have direction, unlike most other VCS. It doesn't matter if you merge the development branch into the master branch or the development branch into the master branch. The result should be the same.
Summary:
Choosing rebase over merge or the other way around is a per-basis choice but it is a choice that has effects. This is a good resource for helping you decide.