Ancient history is the aggregate of past events WordNet Search - 3.0, "History" from the beginning of recorded human history to the Early Middle Ages or the Postclassical Era. The span of recorded history is roughly 5,000 years, with Cuneiform script, the oldest discovered form of coherent writing, from the protoliterate period around the 30th century BC.see Jemdet Nasr period, Kish tablet; see also The Origin and Development of the Cuneiform System of Writing, Samuel Noah Kramer, Thirty Nine Firsts In R..
A coupling (or a coupler) is a mechanism for connecting rolling stock in a train. The design of the coupler is standard, and is almost as important as the track gauge, since flexibility and convenience are maximised if all rolling stock can be coupled together.
