The biggest contribution of the Phoenicians to the history of the world was their development of the alphabet.
Its origins lie in the southern Levant around 1700 BC - the alphabetic signs themselves were adapted from Egyptian hieroglyphs. They became established throughout the Levant (alongside cuneiform) from the 15th century BC, and were used by the Canaanites and their descendants, the Phoenicians.
The first long alphabetic texts are those of the Phoenicians, dating to the 12th or 11th century BC. Having twenty-two consonants, the Phoenician alphabet became the basis for Hebrew, Syriac, Arabic and other alphabetic scripts of West Asia.
It was adopted by the Greeks, who added vowels; this spread throughout western civilization, and was the foundation for the English alphabet which we use today.