Question

who invented ABCDEFGHIJKLMNOPQRSTUVWXYZ

Answer 1

By at least the 8th century BCE the Greeks borrowed the Phoenician alphabet and adapted it to their own language, creating in the process the first "true" alphabet, in which vowels were accorded equal status with consonants. According to Greek legends transmitted by Herodotus, the alphabet was brought from Phoenicia to Greece by Cadmos. The letters of the Greek alphabet are the same as those of the Phoenician alphabet, and both alphabets are arranged in the same order.However, whereas separate letters for vowels would have actually hindered the legibility of Egyptian, Phoenician, or Hebrew, their absence was problematic for Greek, where vowels played a much more important role. The Greeks used for vowels some of the Phoenician letters representing consonants which weren't used in Greek speech. All of the names of the letters of the Phoenician alphabet started with consonants, and these consonants were what the letters represented, something called the acrophonic principle.

Answer 2

The Glagolitic alphabet is believed to have been created by Saints Cyril and Methodius, while the Cyrillic alphabet was invented by Clement of Ohrid, who was their disciple.