The Phoenicians are not the ancient world’s most famous nation, but people who know them, are almost always aware that they invented the alphabet. When in 2007/2008 the Institut du Monde Arabe organized an exposition about the Phoenicians, Paris was full with posters asking inviting questions like “Quel visage avait la civilisation qui nous a donné l’alphabet?”
However, it is not true that the Phoenicians invented the alphabet, although the error is venerably ancient. The ancient Greeks already believed it, and made jokes about it. When the sophist Hadrian of Tyre delivered his inaugural address in Athens, he modestly started his speech with the words “Again, letters have come from Phoenicia”.
Still, the alphabet is much older. In 1904-1905, the famous Egyptologist Sir William Flinders Petrie (1853-1942) discovered alphabetic inscriptions in the Sinai desert. They were older than anything written in Phoenician. In 1998, his American colleague John Darnell discovered texts that were even more ancient; the inscription from the Wadi el-Hol are, for the moment, incomprehensible, but the oldest we have. They date back to c.1900 BCE.
So, the alphabet was invented in Egypt, was applied in the Sinai, was adapted by the Hebrews and the Phoenicians, who gave it to the Greeks.