Western world
There have been many conflicting attempts to enumerate the generations of the western world.. Here are a few common definitions:
The Lost Generation, primarily known as the Generation of 1914 in Europe, were those who fought in the First World War.
The Interbellum Generation is composed of those born at the close of the 19th century and were young adults during the 1920s.
The Greatest Generation is the generation that includes the veterans who fought in World War II. They were born from around 1910 to the mid-1920s, coming of age during the Great Depression. Journalist Tom Brokaw dubbed this the Greatest Generation in a 1998 book of the same name.
The Silent Generation is the generation that includes those who were too young to join the service during World War II. Many had fathers who served in World War I. Generally recognized as the children of the Great Depression, this event during their formative years had a profound impact on this generation.
The Baby Boom Generation is the generation that was born during World War II to the late 50s, a time that was marked by an increase in birthrates worldwide.[citation needed] Baby Boomers in their teenage and college years were characteristically part of the counterculture of the 1960s, the generation remained widely committed to keystone values such as gender equality, racial equality, and environmental stewardship.
Generation X is the generation generally defined as those born after the baby boom ended, extending from around 1960 to the late 1970s. They were the first generation with widespread access to television during their formative years. Other names used interchangeably with Generation X are Reagan Generation, 13th Generation, and Baby Busters. As young adults, this generation was characterized by the Yuppies, or young urban proffesionals.
Generation Y is also known as Generation Next or the Millennials. Generation Y spans from the late 1970s to the early 1990s. This generation will probably be largely defined by the spread of portable media devices and being "always connected". The formative years of this generation saw the advent of personal computers and home video gaming systems.
The following Generation, referred to as Generation Z, and various other names, was born between the mid-1990s and end of the 2000s, and are still being born.
Eastern world
China's Generation Y is a generation of approximately 240 million people born between 1980 and 1990 in China, although characteristics of Generation Y people have also been seen in those born after 1990 but before 2000. Growing up in modern China, China’s Gen Y has been characterized by its optimism for the future, newfound excitement for consumerism and entrepreneurship and acceptance of its historic role in transforming modern China into an economic superpower.
In South Korea generational cohorts are often defined around the democratization of the country, with various schemes suggested, some names include the democratization generation, 386 generation (also called June 3, 1987 Generation), that witnessed the June uprising, the April 19 generation (that struggled against the Syngman Rhee regime in 1960), the June 3, generation (that struggled against the normalization treaty with Japan in 1964), the 1969 generation (that struggled against the constitutional revision allowing three presidential terms), and shinsedae (new) generation.
The full article, from Wikipedia, can be found here