A set of written symbols or characters used to represent the sounds of a language. Each character in an alphabet usually represents a single sound rather than a syllable or group of vowels or consonants. The first alphabets were devised around the eastern shores of the Mediterranean around 1700-1500 BC. The Phoenicians developed what is known as North Semitic and it is considered the ancestor of all modern alphabets. However, Semitic language scripts used only consonants. The Greeks then added vowels when they adopted an alphabet in c 8th century BC. The number of letters in an alphabet varies from 20-30 to hundreds for hieroglyphic and cuneiform scripts to thousands for Chinese in which every sign is an ideogram.