Alpha in the context of "English alphabet"

The Greek alphabet has been used to write the Greek language since the late 9th or early 8th century BC. It was derived from the earlier Phoenician alphabet, and is the earliest known alphabetic script to systematically write vowels as well as consonants. In Archaic and early Classical times, the Greek alphabet existed in many local variants, but, by the end of the 4th century BC, the Ionic-based Euclidean alphabet, with 24 letters, ordered from alpha to omega, had become standard throughout the Greek-speaking world and is the version that is still used for Greek writing today.

The uppercase and lowercase forms of the 24 letters are:

Transliteration is a type of conversion of a text from one script to another that involves swapping letters (thus trans- + liter-) in predictable ways, such as Greek ⟨α⟩ → ⟨a⟩ and ⟨χ⟩ → the digraph ⟨ch⟩, Cyrillic ⟨д⟩ → ⟨d⟩, Armenian ⟨ն⟩ → ⟨n⟩ or Latin ⟨æ⟩ → ⟨ae⟩.

For instance, for the Greek term ⟨Ελληνική Δημοκρατία⟩, which is usually translated as 'Hellenic Republic', the usual transliteration into the Latin script (romanization) is ⟨Hellēnikḗ Dēmokratía⟩; and the Russian term ⟨Российская Республика⟩, which is usually translated as 'Russian Republic', can be transliterated either as ⟨Rossiyskaya Respublika⟩ or alternatively as ⟨Rossijskaja Respublika⟩.

A, or a, is the first letter and the first vowel letter of the Latin alphabet, used in the modern English alphabet, and others worldwide. Its name in English is a (pronounced /ˈeɪ/ AY), plural aes.

It is similar in shape to the Ancient Greek letter alpha, from which it derives. The uppercase version consists of the two slanting sides of a triangle, crossed in the middle by a horizontal bar. The lowercase version is often written in one of two forms: the double-storey |a| and single-storey |ɑ|. The latter 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.

Alpha particles, also called alpha rays or alpha radiation, consist of two protons and two neutrons bound together into a particle identical to the nucleus of a helium-4 atom. They are generally produced in the process of alpha decay but may also be produced in different ways. Alpha particles are named after the first letter in the Greek alphabet, α. The symbol for the alpha particle is α or α. Because they are identical to helium nuclei, they are also sometimes written as He or
₂He indicating a helium ion with a +2 charge (missing its two electrons). Once the ion gains electrons from its environment, the alpha particle becomes a normal (electrically neutral) helium atom
₂He.

Alpha particles have a net spin of zero. When produced in standard alpha radioactive decay, alpha particles generally have a kinetic energy of about 5 MeV and a velocity in the vicinity of 4% of the speed of light. They are a highly ionizing form of particle radiation, with low penetration depth (stopped by a few centimetres of air, or by the skin).

In physics, angular acceleration (symbol α, alpha) is the time rate of change of angular velocity. Following the two types of angular velocity, spin angular velocity and orbital angular velocity, the respective types of angular acceleration are: spin angular acceleration, involving a rigid body about an axis of rotation intersecting the body's centroid; and orbital angular acceleration, involving a point particle and an external axis.

Angular acceleration has physical dimensions of angle per time squared, with the SI unit radian per second squared (rad⋅s). In two dimensions, angular acceleration is a pseudoscalar whose sign is taken to be positive if the angular speed increases counterclockwise or decreases clockwise, and is taken to be negative if the angular speed increases clockwise or decreases counterclockwise. In three dimensions, angular acceleration is a pseudovector.

Ayb (majuscule: Ա; minuscule: ա; Armenian: այբ) is the first letter of the Armenian alphabet. It has a numerical value of 1. It represents the [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 (aybuben), 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.