Those images are called “glyphs” and are part of a “glyph code,” where each image and position of the yellow dot on the image corresponds to a different letter in the alphabet.

Humans Help to unlock the secrets of written language by playing Glyph. Spot visual patterns in humanity’s many scripts and boost the science exploring graphical communication with the online ...

The alphabet, as best as historians can tell, got its start in ancient Egypt sometime in the Middle Bronze Age, ... While the glyphs were sort of alphabetic in nature, ...