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# A

The letter A is the first letter in the Latin alphabet.

 Contents

## History

The letter A probably started as a pictogram of an ox head in Egyptian hieroglyphs or the Proto-semitic alphabet.

 Egyptian hieroglyphox head Proto-semiticox head Phoenician aleph Greek alpha Etruscan A Roman A

By 1600 BC, the Phoenician alphabet's letter had a linear form that served as the basis for all later forms. Its name must have corresponded closely to the Hebrew aleph.

When the Ancient Greeks adopted the alphabet, they had no use for the glottal stop that the letter had denoted in Phoenician and other Semitic languages, so they used the sign for the vowel , and changed its name to alpha. In the earliest Greek inscriptions, dating to the 8th century BC, the letter rests upon its side, but in the Greek alphabet of later times it generally resembles the modern capital letter, although many local varieties can be distinguished by the shortening of one leg, or by the angle at which the cross line is set.

The Etruscans brought the Greek alphabet to what was Italy and left the letter unchanged. The Romans later adopted the Etruscan alphabet to write Latin, and the resulting letter was preserved in the modern Latin alphabet used to write many languages, including English.

## Typography

The modern lowercase letter a derives from Greek handwriting, which evolved from a form similar to the current capital to a circular shape with a projection by the 4th century.

 Blackletter A Uncial A Modern Roman A Modern Italic A Modern Script A

## Usage

In English, the letter A by itself usually denotes the lax open front unrounded vowel (IPA /æ/) as in pad, the open back unrounded vowel (IPA /ɑ/) as in father, or, in concert with a later e, the diphthong /eɪ/ (though the actual pronunciation depends on the dialect) as in ace, due to effects of the Great vowel shift.

In most other languages that use the Latin alphabet, the letter A denotes either an open back unrounded vowel (IPA /ɑ/), or an open central unrounded vowel (IPA /a/).

In the International Phonetic Alphabet, variants of the letter A denote various vowels. In X-SAMPA, capital A denotes the open back unrounded vowel and lowercase a denotes the open front unrounded vowel.

## Alternate representations

In the NATO phonetic alphabet the letter A is Alfa (which may also be spelled Alpha in English-only environments).

In international Morse code the letter A is DitDah: · -

In Braille the letter A is represented as (in Unicode), the dot pattern:

```X.
..
..
```

### Computing

In Unicode the capital A is codepoint U+0041 and the lowercase a is U+0061.

The ASCII code for capital A is 65 and for lowercase a is 97; or in binary 01000001 and 01100001, correspondingly.

The EBCDIC code for capital A is 193 and for lowercase a is 129.

The numeric character references in HTML and XML are "&#65;" and "&#97;" for upper and lower case respectively.