KAF (Heb. כ ,ך ;כָּף), the eleventh letter of the Hebrew alphabet; its numerical value is 20. In the Proto-Sinaitic and early Proto-Canaanite inscriptions the kaf was drawn as a pictograph of the palm of the hand and hence its name. In the later Proto-Canaanite and in the early Phoenician scripts the letter was represented by three fingers meeting at a common base . From the late tenth century b.c.e. and onward a downstroke was added . The kaf developed in the various branches the following variations: , , , (Phoenician);, , (Hebrew); and , , (Aramaic). From the fourth century b.c.e. Aramaic script the kaf (as well as mem, nun, pe, and ẓadi) in medial position began to bend its downstroke to the left, toward the next letter within the word, and the long downstroke was used only in the final forms. The distinction, which survived also in Syriac and Nabatean, is clear in the Jewish script: (medial), (final).
The Greek kappa – the ancestor of the Latin "K" – developed from the ninth-century Phoenician kaf. See *Alphabet, Hebrew.
"Kaf." Encyclopaedia Judaica. . Encyclopedia.com. (September 18, 2018). http://www.encyclopedia.com/religion/encyclopedias-almanacs-transcripts-and-maps/kaf
"Kaf." Encyclopaedia Judaica. . Retrieved September 18, 2018 from Encyclopedia.com: http://www.encyclopedia.com/religion/encyclopedias-almanacs-transcripts-and-maps/kaf