[Openurmind]

Mesopotamia was before those. And the Indus Valley Harappan Script was before them.

[Verginius Rufus]

There were a number of scripts invented before the alphabet--in Mesopotamia, Egypt, India, China. But they were all complicated systems used by a small number of scribes. The alphabet was different in having just a small number of symbols (22 in the Phoenician and Hebrew versions) so literacy could be widespread.

No one knows how to decipher the Harappan script. So we don't even know if they had Ovaltine.

The Bronze Age inhabitants of Greece had at least two writing systems (now called Linear A and Linear B) but they were syllabic systems and probably only a limited number of people knew them. The script on the Phaistos Disk seems to be a different system entirely. There was a syllabic system derived from one of the Bronze Age systems that continued in use in Cyprus much later even when other Greeks had an alphabet.

Linear A and Linear B died out entirely and have no connection to the later Greek alphabet (which was derived from the Phoenician alphabet). Linear B can now be mostly read thanks to Michael Ventris' decipherment in 1952.