The terms BCE (Before Common Era) and CE (Common Era) are increasingly being used as academic forms of BC (Before Christ) and AD (Anno Domini). Both systems take the Gregorian calendar as their starting point.

A similar looking tablet bearing the same inscription in the British Museum collection states that it is probably a 20th Century plaster copy of an original tablet.

In line 5, Sîn-kašid is described as the ‘provider for É-anna’ (or ‘the House of Heaven’), which was the major temple of Anu and Inanna/Ištar in Uruk. The mention of this important temple here also suggests that this tablet originated in Uruk.

The term Common Era was first invented in the sixth century AD.

Cuneiform is a system of writing first developed by the ancient Sumerians of Mesopotamia c. 3500–3000 BCE. It is considered the most significant among the many cultural contributions of the Sumerians and the greatest among those of the Sumerian city of Uruk, which advanced the writing of cuneiform c. 3200BCE.

Joshua J Mark, Cuneiform in Ancient History Encyclopedia, 2011

http://www.ancient.eu/cuneiform/

The term cuneiform comes from the Latin word cuneus for ‘wedge’ owing to the wedge-shaped style of writing. 

In cuneiform, a carefully cut writing implement known as a stylus is pressed into soft clay to produce wedge-like impressions that represent word-signs (pictographs) and, later, phonograms or 'word-concepts' (closer to a modern day understanding of a 'word').

Line 4 states that Sîn-kašid was also the leader of the Amnanum tribe.

All of the great Mesopotamian civilizations used cuneiform (the Sumerians, Akkadians, Babylonians, Elamites, Hatti, Hittites, Assyrians, Hurrians and others) until it was abandoned in favour of the alphabetic script at some point after 100 BCE.

Military styled Amorite tribes dominated this era of Mesopotamian history, infiltrating and ruling a number of cities such as Babylon, Aššur and Mari. It seems Sîn-kašid’s rise to power should be seen in this light.