Letters of the Alef-Beit
Forms of the Letters as written in the Torah scroll, Tefilin & Mezuzah (27 classes)
Aleph
Kaf (kefufah, "bent over" as in beginning or middle of word)
Kaf (peshutah, "straightened out" as at the end of a word)
Mem (petuhah, "open" as in beginning or middle of word)
Mem (s'tumah, "closed" as at the end of a word)
Nun (kefufah, "bent over" as in beginning or middle of word)
Nun petuhah, "straightened out", "end" Nun as at the end of a word)
Peh (kefufah, "bent over", as in beginning or middle of word)
Peh (p'shutah, "straightened", as at end of word)
Tzadi (kefufah, "bent over", as in beginning or middle of word
Tzadi (p'shutah, "straightened, as at end of word)
Study Aid: Hebrew
Alphabet used in writing Torah Scroll, Tefilin
and Mezuzot by Rabbi Yisroel Dovid Berger
Mishnat
Sofrim (by Chofetz Chaim, translated by Rabbi Jona Vogel) on
the laws of the forms of the Hebrew letters