Kaph

The letter kaf is one of the six letters that can receive a dagesh kal. The other five are bet, gimel, daleth, pe, and tav (see Hebrew Alphabet for more about these letters).

There are two orthographic variants of this letter that alter the pronunciation:

When the kaph has a "dot" in its center, known as a dagesh, it represents a voiceless velar plosive ([k]). There are various rules in Hebrew grammar that stipulate when and why a dagesh is used.

When this letter appears as כ‎ without the dagesh ("dot") in its center it represents [χ], like the ch in German "Bach".

In modern Israeli Hebrew the letter heth is often pronounced as a [χ], but many communities (particularly those of Mizrahi and Sephardi origins, as well as immigrants to Israel from Arab countries and Arab Israelis) have differentiated between these letters as in other Semitic languages.

Orthographic variants
Various Print Fonts			Cursive Hebrew	Rashi script
Serif	Sans-serif	Monospaced
ך	ך	ך

If the letter is at the end of a word the symbol is drawn differently. However, it does not change the pronunciation or transliteration in any way. The name for the letter is final kaf (kaf sofit). Four additional Hebrew letters take final forms: tsadi, mem, nun, and pei. Kaf/khaf is the only Hebrew letter that can take a vowel in its word-final form, which is pronounced after the consonant, that vowel being the qamatz.

In gematria, kaph represents the number 20. Its final form represents 500, but this is rarely used, tav and qoph (400+100) being used instead.

As a prefix, kaph is a preposition:

• It can mean "like" or "as", as in literary Arabic (see below).
• In colloquial Hebrew, kaph and shin together have the meaning of "when". This is a contraction of כַּאֲשֶׁר‎, ka'asher (when).

In Literary Arabic, kāf is used as a prefix meaning "like", "as", or "as though". For example, كَطَائِر (/katˤaːʔir/), meaning "like a bird" or "as though a bird" (as in Hebrew, above). The prefix كَـ ka is one of the Arabic words for "like" or "as" (the other, مِثْل /miθl/, is unrelated). The /ka/ prefix sometimes has been added to other words to create fixed constructions. For instance, it is prefixed to ذٰلِك /ðaːlik/ "this, that" to form the fixed word كَذٰلِك /kaðaːlik/ "like so, likewise."

kāf is used as a possessive suffix for second-person singular nouns (feminine taking kāf-kasrah كِ, /ki/ and masculine kāf-fatḥah كَ /ka/); for instance, كِتَاب kitāb ("book") becomes كِتَابُكَ kitābuka ("your book", where the person spoken to is masculine) كِتَابُكِ kitābuki ("your book", where the person spoken to is feminine). At the ends of sentences and often in conversation the final vowel is suppressed, and thus كِتَابُك kitābuk ("your book"). In several varieties of vernacular Arabic, however, the kāf with no harakat is the standard second-person possessive, with the literary Arabic harakah shifted to the letter before the kāf: thus masculine "your book" in these varieties is كِتَابَك kitābak and feminine "your book" كِتَابِك kitābik.