E

Latin alphabet
	Aa	Bb	Cc	Dd
Ee	Ff	Gg	Hh	Ii	Jj
Kk	Ll	Mm	Nn	Oo	Pp
Qq	Rr	Ss	Tt	Uu	Vv
	Ww	Xx	Yy	Zz

The letter E is the fifth letter in the Latin alphabet.

Contents

1 History

2 Usage

3 Alternate representations

3.1 Computing

4 Meanings for E

5 See also

History

E is derived from the Greek letter epsilon which is much the same in appearance (Ε, ε) and function. The Semitic hê probably first represented a praying or calling human figure. In Semitic, the letter was pronounced /h/ (in foreign words also /e/), in Greek hê became Εψιλον (Epsilon) with the value /e/. Etruscans and Romans followed this usage. Due to the Great Vowel Shift, English usage is rather different, namely /i:/ in ME or BEE, whereas other words like BED are quite close to Latin or Continental European usage.

Usage

Like other Latin vowels, e came in a long (sounded as in thee) and a short variety (sounded as in pet). In other languages which use the letter it takes on various other values, sometimes with accents to indicate which one (ê,é,è,ë).

This is the most common letter in English and many related languages, which has some implications in Cryptography.

Alternate representations

Echo represents the letter E in the NATO phonetic alphabet.

In international Morse code the letter E is Dit: ·

In Braille the letter E is represented as ⠑ (in Unicode), the dot pattern,

X.
.X
..

Computing

In Unicode the capital E is codepoint U+0045 and the lowercase e is U+0065.

The ASCII code for capital E is 69 and for lowercase e is 101; or in binary 01000101 and 01100101, correspondingly.

The EBCDIC code for capital E is 197 and for lowercase e is 133.

The numeric character references in HTML and XML are "E" and "e" for upper and lower case respectively.

Meanings for E

In the atmosphere of Earth, the E layer is part of the ionosphere.
In biochemistry, E is the symbol for glutamic acid and also often an abbreviation for enzyme.
In computing, the letter e (with or without a subsequent hyphen) is often used as a prefix for other words to imply "electronic," such as e-mail or e-commerce.
In computational complexity theory, the complexity class E.
In currency, e is commonly used symbol for the euro when the symbol € is not available.
In English slang, e is often used as an abbreviation of ecstasy, a synthetic drug.
In film, E is a Canadian film from 1982; see E (film).
In finance securities, E is stock symbol for ENI Spa
In gender-neutral pronouns, e is the Spivak pronoun meaning he or she.
In international licence plate codes, E stands for Spain (España).
In mathematics,
- e is Euler's number, a transcendental number (approximately equal to 2.71828182846) which is used as the base for natural logarithms. See e (mathematical constant).
- E is also used to signify ×10^y; i.e. 7e8 is 7×10⁸ or 700,000,000.
- E is often used as a digit meaning fourteen in hexadecimal and other positional numeral systems with a radix of 15 or greater.
In the Metric system, E, exa, is the SI prefix meaning 10¹⁸.
In music, E is a note.
In physics, E is,
- The symbol for energy, as in E = mc².
- The symbol for electric field.
- In particle physics, e is the symbol for the electron.
In probability and statistics, a capital E denotes expected value.
In structural engineering E stands for the modulus of elasticity.
In symbolic logic $\exists$ (a backwards E) is the symbol for "there exists...", called the existential quantifier. Example: $\exists x\,(x+1=3)$ .
In video games, E is the ESRB rating symbol for Everyone.
鄂, or È is an abbreviation for the Hubei province of the People's Republic of China.
E is the pseudonym of Mark Oliver Everett, lead singer of The Eels.