What Does It Mean?

You are correct!

From our dictionary:
di•dac•tic

(dI•dak'tik),
adj.
1. intended for instruction; instructive: didactic poetry.
2. inclined to teach or lecture others too much: a boring, didactic speaker.
3. teaching or intending to teach a moral lesson.
4. didactics, (used with a sing. v.) the art or science of teaching. Also,di•dac'ti•cal.