Hebrew alphabet written from right to left. It has 22 letters, five of which use different forms at the end of a word. In the traditional form, vowels are indicated by the weak consonants Aleph (), He (), Vav (), or Yodh () serving as vowel letters, or "matres lectionis": the letter is combined with a previous vowel and becomes silent, or by imitation of such cases in the spelling of other forms. Also, a system of vowel points to indicate vowels (diacritics), called niqqud, was developed. In modern forms of the alphabet, as in the case of Yiddish and to some
Hebrew alphabet letters "came with the Israelites from Ashur [Assyria]"); others attribute mystical significance to the letters, connecting them with the process of creation or the redemption. In mystical conceptions, the alphabet is considered eternal, pre-existent to the Earth, and the letters themselves are seen as having holiness and power, sometimes to such an extent that several stories from the Talmud illustrate the idea that they cannot be destroyed. The idea of the letters' creative power finds its greatest vehicle in the Sefer Yezirah, or "Book of Creation", a mystical text of uncertain origin which describes a story of creation highly divergent