There is no scientific reason for a generational breakdown, these labels are only used by older individuals as a device of condescension and criticism to be used on the youth to shame them for their normal stages of development.
Millennials are the most recent in a series of labeled generations in American History. The 6 living generations being: The Greatest Generation (1900-20), The Silent Generation (1920-40), The Baby Boomers (1940-60), Generation X (1960-80) and finally Generation Y, or Millennials. The United States census department does not define generations, which brings into question who really benefits from the use of such labels. The term "Millennials" was coined by two gentleman named Neil Howe and William Strauss. Strauss was an American author, historian, playwright, theater director, and lecturer and Howe was an American historian, economist, and demographer. These men worked together to write the book Generations in 1991 in which they coined the term Millennials. They now consult big businesses such as Best Buy and the Coast Guard on ad campaigns and services aimed toward Millennials, they are using the term to make money. The term "Generation X" was coined by Douglas