The Hebrew alphabet has 22 letters. Five Hebrew letters are formed differently when they appear as the last letter of a word. These forms are called “sofit”(final) forms. The five letters sound the same as their non-sofit cousins and they are:
Kaf- ך , Mem- ם, Nun- ן, Fe- ף,Tzadi- ץ.
In the Hebrew Alphabet, there are also four guttural letters. The word guttural literally means ‘of the throat’, and is derived from the Latin word for throat. It refers to a pronounced or heavy sound that emanates from the pharynx and up from the back of the throat and has a certain kind of very heavy and pronounced “throaty” quality.
The four guttural letters are:
Aleph- א, Hey- ה, Chet- ח, Resh- ר.
The concept of gutturality is not entirely objective, but a guttural sound is generally believed to be one, which is pronounced with the dorsum of the tongue and/or at any point behind the hard palate, including the soft palate, the uvula or the pharynx. In scientific discourse, the more precise terms indicating the place of articulation, such as uvular consonant, are generally preferred.