If you are about my age, this diagram may be familiar to you. It used to be found in many Chabad publications, and I assume that it was originally produced and published by Merkos L'inyonei Chinuch, the Chabad educational organization, as a classroom poster.
It's a great educational tool, laying out the basic mesorah (tradition) of the Torah. Beginning with Sinai and the Written Torah, it works through the Mishna, Talmud, and major poskim (authorities in Jewish law). I remember, as a young boy, that this poster was my first introduction to the existence of such important works as the Rif and Tur. In my experience, as a teacher, most middle-school students, even in good yeshivos, are often not familiar with this basic information.
For some reason, the poster is now very difficult to find. If anyone has any info about it, please let me know.