The Sumerians had cuneiform and the Egyptians hieroglyphics, both complex and difficult to master, but who developed the system where each character represents a particular sound and the characters (letters) can be combined to form words the way sounds are? The Phoenicians invented the alphabet from which all the European and Near Eastern scripts (and possibly those of India as well) are descended, but they didn’t come up with the idea. Who did? Very likely, a bunch of common laborers. – Smithsonian Magazine
