Writing is undeniably one of humanity's most important inventions. The earliest forms of storing information on objects were numerical inscriptions on clay tablets, used for administration, accounting and trade. The first writing system dates back to around 3000 BC, when the Sumerians developed the first type script: hundreds of abbreviated pictograms that could be pressed into clay.
Individual symbols for nouns, verbs, and adjectives followed. These symbols were eventually refined and simplified. As round shapes were hard to etch into clay, they were replaced by lines, and depressions were made at the beginning of the line, creating the unique style known to us as cuneiform script.
The first writing was done from top to bottom, but left to right writing was adopted around 2400 BC, simply by rotating the symbols by 90 degrees. The ingenious invention of writing traveled and was adopted by the Egyptians (in the form of hieroglyphs), the Elamites (who modified it slightly), and finally the Akkadians.
The Akkadians modified the Sumerian writing system so that every sign represents a syllable, which brings us another step closer to a modern alphabet. Eventually, syllabic cuneiform was adopted across different languages all over western Asia, including in Babylon, Ugarit, and Hattusas.
Cuneiform writing from Assyria.