The capital letters of the modern greek alphabet is almost the same as lonic alphabet. Lower case letters came to be in after 800 AD. People would usually write horizontal lines and write, right to left. In 500 bc changed the direction of writing to horizontal lines from left to right.
The Greek alphabet has been used since 8th century BC. It was mostly derived from the earlier Phoenician alphabets and was the first alphabetic script to have distinct letters for vowels as well as consonants.