Stam letters. These are the two major writing styles used in Jewish sacramental practice (Torah scrolls, mezuzahs etc): Ashkenazic and Sephardic. Ashkenazi style is used by the Jews of North and East European origin. Sephardic - by Jews of Spanish, Southern European origin and all the Jewish people from Muslim countries.
Ashkenazic scripts has a Hassidic (Jewish mysticism movement) version - 7 letters differ slightly. In the video I forgot to show one of these letters - Shin. The difference of the Hassidic