| Armenian letter Ayb | |
| Letter: | Ա ա |
| Imagealt: | Typographic upper and lower case of the letter Ayb |
| Imagesize2: | 133px |
| Imagealt2: | Handwritten upper and lower case of the letter Ayb |
| Script: | Armenian script |
| Type: | Alphabet |
| Typedesc: | ic |
| Language: | Armenian language |
| Phonemes: | pronounced as /ink/ |
| Unicode: | U+0531, U+0561 |
| Alphanumber: | 1 |
| Number: | 1 |
| Fam1: | Possibly, Α α |
| Usageperiod: | 405 to present |
Ayb (majuscule: Ա; minuscule: ա; Armenian: այբ) is the first letter of the Armenian alphabet. It has a numerical value of 1.[1] [2] It represents the [{{IPAlink|ɑ}}] sound in both variants of the Armenian language. This letter and the letter Ben (Բբ) are the two first letters in the Armenian alphabet and forms the etymology of the Armenian word այբուբեն, meaning "alphabet." It is one of the letters originally created by Mesrop Mashtots in the 5th century.
Its prototype is considered to be the Greek letter α (alpha) with the upper arc cut off. A number of Armenian letters are formed in a similar fashion.
It is homoglyphic to the IPA symbol for the close back unrounded vowel, the Cyrillic letter Sha (Шш), the former Zhuang letter Ɯɯ used from 1957 to 1986, and the Nushkuri form of the Georgian letter oni .
The letter Ա is the most common letter in the Armenian alphabet. It occurs mainly in initial or medial word positions and very rarely in final position. This is explained by the fact that the Proto-Armenian language lost word-final vowels in multisyllabic words.
As a unit, it is a symbol of God. This is because the words God—"Աստված", ⟨Astvadz(W.A.), Astvac'(E.A.)⟩—and Creator—"Արարիչ", ⟨Ararich⟩—begin with it. Thus, the symbolism of it corresponds to the Greek letter "alpha" in the Book of Revelation, where the Lord says, "I am Alpha and Omega, the beginning and the end." (1:8 ).