⟨a⟩ is the third-most-commonly used letter in English after ⟨e⟩ and ⟨t⟩, as well as in French; it is the second most common in Spanish, and the most common in Portuguese. However, ⟨a⟩ occurs in many common digraphs, all with their own sound or sounds, particularly ⟨ai⟩, ⟨au⟩, ⟨aw⟩, ⟨ay⟩, ⟨ea⟩ and ⟨oa⟩. There are some other cases aside from italic type where script a ⟨ɑ⟩, also called Latin alpha, is used in contrast with Latin ⟨a⟩, such as in the International Phonetic Alphabet. The Roman form ⟨a⟩ is found in most printed material, and consists of a small loop with an arc over it. In the hands of medieval Irish and English writers, this form gradually developed from a 5th-century form resembling the Greek letter tau ⟨τ⟩.
The Italic form ⟨ɑ⟩, also called script a, is often used in handwriting; it consists of a circle with a vertical stroke on its right. The latter form is commonly used in handwriting and fonts based on it, especially fonts intended to be read by children, and is also found in italic type. Before a vowel sound an is usual These are due to fronting, that is to say, pronouncing the sound more toward the front of the mouth, or to rounding, slightly rounding the lips, which has the effect of causing the sound to be pronounced higher in the mouth. The name of the letter in the Phoenician period resembled the Hebrew name aleph meaning "ox"; the form is thought to derive from an earlier symbol resembling the head of an ox. Once you receive the supplier registration approval notification, as a registered supplier, you can participate in public procurement.
But an also occurs though less frequently now than formerly. A similar fronting of this sound took place in the Ionic-Attic dialects of Greek, where sounds derive from the a-sound and represented in other dialects by a are represented by η. Sound 3 represents a stage in the development of a on its way from 1 to 4 which was arrested at this point when the sound was followed by r.



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