The alphabet is one of the great inventions in the history of civilization.
The cuneiform and hieroglyphic writings systems were ingenious inventions, but they were cumbersome and difficult to learn. A student had to memorize hundreds of signs; consequently literacy was limited to a privileged class of scribes, teachers, and government administrators.
The oldest alphabetic inscriptions are called the “Proto-Sinaitic” inscriptions. They are in a language similar to Hebrew and were written in the mines near Mt. Sinai. They seem to be derived from a simplified list of hieroglyphic signs.
Later, at Ugarit (modern Rash Shamra) a simplified cuneiform list was developed, representing 29 consonants.
Somewhere along the way the Phoenicians developed an alphabet. (Its origin may have had something to do with the Proto-Sinaitic alphabet.) The Phoenicians were sailors and merchants who visited many countries. It was their form of the alphabet that the Hebrews eventually adopted–as did the Greeks. The Hebrews continued writing from right to left, but the Greeks eventually mirror-imaged the signs and started writing from left to write.
Alpu originally meant ‘ox’, beitu meant ‘house,’ gimlu ‘camel’, daltu door, and so forth.
Alpu became Aleph in Hebrew and Alpha in Greek,
Beitu became Bet and Beta, and so on.
The oldest Hebrew inscriptions are written in a script nearly identical to Phoenician.
Do a google search, or go to Wikipedia to see some pictures and learn a little more about Ugaritic, Phoenician, Proto-Sinaitic, and other related subjects.