The wonderfully plain-spoken animated statistical series The Infographics Show explained the history of nomenclature, citing the likely origins of the very first names and the derivatives thereof. They also provided a fascinating and current list of the most popular names in countries around the world.
First of all we should point out that a lot of Western names originate in the Bible and are slightly different in each language they are used. The name John for instance comes from the Hebrew name of Johannan. It means Yahweh is gracious. Johannan certainly had legs becoming John, Juan, Jan, Johan, Jones, Jean, Jens Hans Janis and more. The name Jack was actually a nickname for John but later it became a name in itself.