Gematria is a numeric system, occasionally cited in the Talmud and more often in kabbala, in which each Hebrew letter has a number value. Aleph=1, bet=2, gimel=3, dalet=4, hei=5, vav=6, zayin=7, chet=8, tet=9, yud=10, kaf=20, lamed=30, mem=40, nun=50, samekh=60, ayin=70, pei=80, tzadi=90, kuf=100, reish=200, shin=300, tav=400. The final letters and even the vowel points also have number values, but these are rarely used.

It should be mentioned that gematria is not to be used to prove things or to create new concepts. Rather, it may occasionally be cited to bolster a bit of Jewish law or exegesis which stands on its own merits (tradition) and does not rely on numerology alone.