The Greek alphabet is an alphabet that has been used to write the Greek language since about the 9th century BC. It was the first true alphabet, that is, an alphabet with a symbol for each vowel and consonant, and is the oldest alphabetic script in use today.

It consists of 24 letters .

Note:
Several letter combinations have special conventional sound values different from those of their single components. Among them are several digraphs of vowel letters that formerly represented diphthongs but are now monophthongized

In the picture you can see the Greek alphabet . The first column  shows the lower case and the second column the upper case of a letter   , in the third column is given the Greek name for each letter while the fourth and fifth column help the English speaker with the pronunciation of each letter .
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