<P> Karl Mannheim, in his 1952 book Essays on the Sociology of Knowledge asserted the belief that people are shaped through lived experiences as a result of social change . Howe and Strauss also have written on the similarities of people within a generation being attributed to social change . Based on the way these lived experiences shape a generation in regard to values, the result is that the new generation will challenge the older generation's values, resulting in tension . This challenge between generations and the tension that arises is a defining point for understanding generations and what separates them . </P> <P> For the purposes of this list, "Western world" can be taken to include North America, Western Europe, Australia and New Zealand . Many variations may exist within these regions, both geographically and culturally, which means that the list is broadly indicative, but necessarily very general . The contemporary characterization of these cohorts used in media and advertising borrows from the Strauss--Howe generational theory among others . </P> <Ul> <Li> The Lost Generation, also known as the Generation of 1914 in Europe, is a term originating with Gertrude Stein to describe those who fought in World War I . The members of the lost generation were typically born between 1883 and 1900 . </Li> <Li> The G.I. Generation, is the generation that includes the veterans who fought in World War II . They were born from around 1901 to 1924, coming of age during the Great Depression . Journalist Tom Brokaw described U.S members of this cohort as the "greatest generation" in a book of the same name . </Li> <Li> The Silent Generation, also known as the Lucky Few, were born from approximately 1925 to 1942 . It includes some who fought in World War II, most of those who fought the Korean War and many during the Vietnam War . </Li> <Li> The Baby Boomers are the generation that were born mostly following World War II . There are no precise dates when the cohort birth years start and end . Typically, they range from the early - to - mid 1940s and end from 1960 to 1964 . Increased birth rates were observed during the post--World War II baby boom making them a relatively large demographic cohort . </Li> <Li> Generation X, commonly abbreviated to Gen X, is the generation following the baby boomers . Demographers and researchers typically use starting birth years ranging from the early - to - mid 1960s and ending birth years in the early 1980s . The term has also been used in different times and places for a number of different subcultures or countercultures since the 1950s . <Ul> <Li> In the U.S., some called Generation Xers the "baby bust" generation because of the drop in the birth rate following the baby boom . The drop in fertility rates in America began in the late 1950s . But according to authors and demographers William Strauss and Neil Howe (who use 1961 to 1981 for Gen X birth years), there are approximately 88.5 million Gen Xers in the U.S. today . </Li> </Ul> </Li> <Li> Millennials, also known as Generation Y, are the cohort of people following Generation X . There are no precise dates for when this cohort starts or ends; demographers and researchers typically use the early 1980s as starting birth years and the mid 1990s to early 2000s as ending birth years . According to Pew Research, as of April 2016 the Millennials surpassed the Baby Boomers in size in the U.S., with 76 million Boomers and 77 million Millennials . </Li> <Li> Generation Z, also known as the iGeneration, Post-Millennials, Homeland Generation, or Plurals is the cohort of people born after the Millennials . Demographers and researchers typically use the mid-1990s to mid-2000s as starting birth years . </Li> </Ul> <Li> The Lost Generation, also known as the Generation of 1914 in Europe, is a term originating with Gertrude Stein to describe those who fought in World War I . The members of the lost generation were typically born between 1883 and 1900 . </Li>

What is the name of the generation before gen x