The Greek alphabet is a set of twenty-four letters that has been used to write the Greek language since the late 9th or early 8th century BCE. It is the first and oldest alphabet in the narrow sense that it notes each vowel and consonant with a separate symbol. It is as such in continuous use to this day. The letters were also used to represent Greek numerals, beginning in the 2nd century BCE.
The Greek alphabet is descended from the Phoenician alphabet, and is not related to Linear B or the Cypriot syllabary, earlier writing systems for Greek. It has given rise to many other alphabets used in Europe and the Middle East, including the Latin alphabet. In addition to being used for writing Modern Greek, its letters are today used as symbols in mathematics and science, particle names in physics, as names of stars, in the names of fraternities and sororities, in the naming of supernumerary tropical cyclones, and for other purposes.
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Uppercase Greek Letters

Lowercase Greek Letters
The Greek alphabet emerged centuries after the fall of the Mycenaean civilization and consequent abandonment of its Linear B script, an early Greek writing system. Linear B is descended from Linear A, which was developed by the Minoans, whose language was probably unrelated to Greek; consequently the Minoan syllabary did not provide an ideal medium for the transliteration of the sounds of the Greek language.
The Greek alphabet we recognize today arose after the Greek Dark Ages — the period between the downfall of Mycenae (ca. 1200 BC) and the rise of Ancient Greece, which begins with the appearance of the epics of Homer, around 800 BC, and the institution of the Ancient Olympic Games in 776 BC. Its most notable change, as an adaptation of the Phoenician alphabet, is the introduction of vowel letters, without which Greek would be illegible.
Vowel signs were originally not used in Semitic alphabets. Whereas in the earlier West Semitic family of scripts (Phoenician, Hebrew, Moabite etc.) a letter always stood for a consonant in association with an unspecified vowel or no vowel; because these languages were Semitic, they lost no legibility in having no vowels, as Semitic words are based on triliteral roots that make meaning clear with only the consonants present, and vowels are clear from context. Greek, however, is an Indo-European language, and thus differences in vowels make for vast differences in meanings. Thus the Greek alphabet divided the letters into two categories, consonants ("things that sound along") and vowels, where the consonant letters always had to be accompanied by vowels to create a pronounceable unit. Although the old Ugaritic alphabet did develop matres lectionis, i.e., use of consonant letters to denote vowels, they were never employed systematically.
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