An era is a period of time that does not have a specific duration, but it is initiated by a certain event whose importance marks a break with the immediately previous period, and in turn ends when a new event of such magnitude breaks with the order established so far. A clear example is the so-called Age of Discovery, which began with the Discovery of America in 1492 and ended in the early 1600s, when most of the planet's territory had already been explored.
