The uppercase letter alpha is not generally used as a symbol because it tends to be rendered identically to the uppercase Latin A. Most occurrences of alpha in science are the lowercase alpha. In aerodynamics, the letter is used as a symbol for the angle of attack of an aircraft and the word "alpha" is used as a synonym for this property. In Attic, the shift did not take place after epsilon, iota, and rho (ε, ι, ρ; e, i, r). In Ancient Greek, alpha was pronounced a and could be either phonemically long (aː) or short (a). Alpha /ˈælfə/ ⓘ ALF-ə (uppercase Α, lowercase α)a is the first letter of the Greek alphabet.

It was derived from the earlier Phoenician alphabet, and is the earliest known alphabetic script to systematically write vowels as well as consonants. Final ρ (r) is preserved before vowels. Each of these is still a "chapter Letter", albeit a double-digit letter just as 10 through 99 are double-digit numbers. Different chapters within καιφας the same fraternity are almost always (with a handful of exceptions) designated using Greek letters as serial numbers.

There were initially numerous local (epichoric) variants of the Greek alphabet, which differed in the use and non-use of the additional vowel and consonant symbols and several other features. The use of both vowels and consonants makes Greek the first alphabet in the narrow sense, as distinguished from the abjads used in Semitic languages, which have letters only for consonants. This leads to several groups of vowel letters denoting identical sounds today. Among the vowel letters, Modern Greek sound values reflect the radical simplification of the vowel system of post-classical Greek, merging multiple formerly distinct vowel phonemes into a much smaller number.

As an organization expands, it establishes a B chapter, a Γ chapter, and so on and so forth. The IPA symbol for the palatal lateral approximant is ⟨ʎ⟩, which looks similar to lambda, but is actually an inverted lowercase y. Several of them denote fricative consonants; the rest stand for variants of vowel sounds. Several Greek letters are used as phonetic symbols in the International Phonetic Alphabet (IPA). Many symbols have traditional uses, such as lower case epsilon (ε) for an arbitrarily small positive number, lower case pi (π) for the ratio of the circumference of a circle to its diameter, capital sigma (Σ) for summation, and lower case sigma (σ) for standard deviation. Greek symbols are used as symbols in mathematics, physics and other sciences.

Antiquity

This iota represents the former offglide of what were originally long diphthongs, ⟨ᾱι, ηι, ωι⟩ (i.e. /aːi, ɛːi, ɔːi/), which became monophthongized during antiquity. The acute accent in aulós avˈlos ('flute') distinguishes the word from its homograph áulos ˈailos ('immaterial'). Modern Greek speakers typically use the same, modern symbol–sound mappings in reading Greek of all historical stages. As a consequence, the spellings of words in Modern Greek are often not predictable from the pronunciation alone, while the reverse mapping, from spelling to pronunciation, is usually regular and predictable. Additionally, Modern and Ancient Greek now use different diacritics, with ancient Greek using the polytonic orthography and modern Greek keeping only the stress accent (acute) and the diaeresis. Sound values and conventional transcriptions for some of the letters differ between Ancient and Modern Greek usage because the pronunciation of Greek has changed significantly between the 5th century BC and the present.

In handwriting, ensure the lowercase α has a clear loop and tail to distinguish it from the Latin a. For the range A0–FF (hex), it follows the Unicode range 370–3CF (see below) except that some symbols, like ©, ½, § etc. are used where Unicode has unused locations. Some letters can occur in variant shapes, mostly inherited from medieval minuscule handwriting. The Roman alphabet has a similar extended form with such double-digit letters when necessary, but it is used for columns in a table or chart rather than chapters of an organization. In an organization that expands to more than 24 chapters, the chapter after Ω chapter is AA chapter, followed by AB chapter, etc.

Mathematics

The classical twenty-four-letter alphabet that is now used to represent the Greek language was originally the local alphabet of Ionia. Epichoric alphabets are commonly divided into four major types according to their different treatments of additional consonant letters for the aspirated consonants (/pʰ, kʰ/) and consonant clusters (/ks, ps/) of Greek. Individual letter shapes were mirrored depending on the writing direction of the current line.

• In the following group of consonant letters, the older forms of the names in Ancient Greek were spelled with -εῖ, indicating an original pronunciation with -ē.
• In handwriting, ensure the lowercase α has a clear loop and tail to distinguish it from the Latin a.
• Apart from its use in writing the Greek language, in both its ancient and its modern forms, the Greek alphabet today also serves as a source of international technical symbols and labels in many domains of mathematics, science, and other fields.
• As an organization expands, it establishes a B chapter, a Γ chapter, and so on and so forth.
• Some letters can occur in variant shapes, mostly inherited from medieval minuscule handwriting.

Such handwriting has been preserved especially from papyrus manuscripts in Egypt since the Hellenistic period. Besides the upright, straight inscriptional forms (capitals) found in stone carvings or incised pottery, more fluent writing styles adapted for handwriting on soft materials were also developed during antiquity. This distinction is an innovation of the modern era, drawing on different lines of development of the letter shapes in earlier handwriting.

During the Renaissance, western printers adopted the minuscule letter forms as lowercase printed typefaces, while modeling uppercase letters on the ancient inscriptional forms. In the 9th and 10th centuries, uncial book hands were replaced with a new, more compact writing style, with letter forms partly adapted from the earlier cursive. The cursive forms approached the style of lowercase letter forms, with ascenders and descenders, as well as many connecting lines and ligatures between letters. In the following group of consonant letters, the older forms of the names in Ancient Greek were spelled with -εῖ, indicating an original pronunciation with -ē. Here too, the changes in the pronunciation of the letter names between Ancient and Modern Greek are regular. The name of lambda is attested in early sources as λάβδα besides λάμβδα; in Modern Greek the spelling is often λάμδα, reflecting pronunciation.

Archaic variants

This system has remained in use in Greek up to the present day, although today it is only employed for limited purposes such as enumerating chapters in a book, similar to the way Roman numerals are used in English. In the classical Ionian system, the first nine letters of the alphabet stood for the numbers from 1 to 9, the next nine letters stood for the multiples of 10, from 10 to 90, and the next nine letters stood for the multiples of 100, from 100 to 900. The symbol in Americanist phonetic notation for the voiceless alveolar lateral fricative is the Greek letter lambda ⟨λ⟩, but ⟨ɬ⟩ in the IPA. Apart from the daughter alphabets listed above, which were adapted from Greek but developed into separate writing systems, the Greek alphabet has also been adopted at various times and in various places to write other languages.

The period between the use of the two writing systems, Linear B and the Greek alphabet, during which no Greek texts are attested, is known as the Greek Dark Ages. This writing system, unrelated to the Greek alphabet, last appeared in the 13th century BC. During the Mycenaean period, between roughly the 16th and 12th centuries BC, a script called Linear B was used to write the earliest attested form of the Greek language, known as Mycenaean Greek. The form in which classical Greek names are conventionally rendered in English goes back to the way Greek loanwords were incorporated into Latin in antiquity.

Sometimes early fraternal organizations were known by their Greek letter names because the mottos that these names stood for were secret and revealed only to members of the fraternity. The name of this fraternal organization is an acronym for the ancient Greek phrase Φιλοσοφία Βίου Κυβερνήτης (Philosophia Biou Kybernētēs), which means "Love of wisdom, the guide of life" and serves as the organization's motto. In North America, many college fraternities and sororities are named with combinations of Greek letters, and are hence also known as "Greek letter organizations". To mark a letter as a numeral sign, a small stroke called keraia is added to the right of it.