Original: The span of early modern European history generally begins from the turn of the 15th century, through the Age of Reason and Age of Enlightenment in the 17th and 18th centuries, until the beginning of the Industrial Revolution in the late 18th century.
Simplified: Generally the term "modern history" refers to the history of the world since the advent of the Age of Reason and the Age of Enlightenment in the 17th and 18th centuries and the beginning of the Industrial Revolution.