The Proto-Sinaitic script is a Middle Bronze Age writing system known from a small corpus of about 30-40 inscriptions and fragments from Serabit el-Khadim in the Sinai Peninsula, as well as two inscriptions from Wadi el-Hol in Middle Egypt. Together with about 20 known Proto-Canaanite inscriptions, it is also known as Early Alphabetic, i.e. the earliest trace of alphabetic writing and the common ancestor of both the Ancient South Arabian script and the Phoenician alphabet, which led to many modern alphabets including the Greek alphabet. According to common theory, Canaanites or Hyksos who spoke a Canaanite language repurposed Egyptian hieroglyphs to construct a different script.

The history of the alphabet goes back to the consonantal writing system used to write Semitic languages in the Levant during the 2nd millennium BCE. Nearly all alphabetic scripts used throughout the world today ultimately go back to this Semitic script. Its first origins can be traced back to a Proto-Sinaitic script developed in Ancient Egypt to represent the language of Semitic-speaking workers and slaves in Egypt. Unskilled in the complex hieroglyphic system used to write the Egyptian language, which required a large number of pictograms, they selected a small number of those commonly seen in their surroundings to describe the sounds, as opposed to the semantic values, of their own Canaanite language. This script was partly influenced by the older Egyptian hieratic, a cursive script related to Egyptian hieroglyphs. The Semitic alphabet became the ancestor of multiple writing systems across the Middle East, Europe, northern Africa, and Pakistan, mainly through Ancient South Arabian, Phoenician and the closely related Paleo-Hebrew alphabet, and later Aramaic and the Nabatean—derived from the Aramaic alphabet and developed into the Arabic alphabet—five closely related members of the Semitic family of scripts that were in use during the early first millennium BCE.