Mesopotamia is derived from the Greek words, mesos meaning "middle," and potamos meaning "river," which became known as the "land between two rivers." Mesopotamia no longer exists today. It is now known as all the land in northern Syria, southern Turkey, and most of Iraq. Researchers believe the peoples of Mesopotamia influenced the development of the human race in many ways.
The Sumerian writing system during the early periods was constantly in flux. The original direction of writing was from top to bottom, but for reasons unknown, it changed to left-to-right very early on (perhaps around 3000 BCE). This also affected the orientation of the signs by rotating all of them 90° counter clockwise.
Another change in this early system involved the "style" of the signs. The early signs were more "linear" in that the strokes making up the signs were lines and curves. But starting after 3000 BCE these strokes started to evolve into wedges, thus changing the visual style of the signs from linear to "cuneiform".
The pictorial script over a period of time eventually developed in the first of alphabets. In Sumer all the writing was done by pictorial representation. The general practice was to represent individual words by unique pictures which actually bore a rough resemblance to the representation.
Pictographs (symbols that visually look like physical objects, also known as hieroglyphs) evolved over time from around 3500 B.C. into Babylonian-Assyrian Cuneiform (wedge shaped writing) around 1800 B.C. Note: The evolution of the pictograph went from the Ancient Sumerians (who developed the first Cuneiform language based on the pictographs) -> Babylonians -> Assyrians. Over time, the original pictograph is in almost all cases, visually unrecognizable in Cuneiform by 600 B.C.
The Greek word 'Babylon' is a rendering of Babillu, a very old word in an unknown language. When Mesopotamia was infiltrated by people who spoke a Semitic language (Akkadians or Amorites), they recognized their own words Bāb ("gate") and ili ("gods") and concluded that this place was 'the gate of the gods'. (A similar etymology was invented for Arbela.)
The Akkadian word shamu can have multiple meanings, depending on its original root origin. The lexical lists above presuppose a shamu that comes from the Akkadian word shama'u or shamamu, both of which mean "heaven," as in a place or portion of the sky.
Notice how similar shamu is to both shama'u and shamamu. Only the extra letter marks them as different, marked either by an apostrophe (shama'u) in English [x] or an "m" (shamamu).