India, March 29 -- The next generation of humans, Gen Beta, begin their lives this year.

Where did the idea of viewing society in such slabs come from?

We can trace it to 1863 and the French lexicographer Emile Littre, who reportedly defined a generation as "all men living more or less in the same time". Before that, the term had been used to signify biological family relationships, typically between fathers and sons.

The American writer Gertrude Stein coined the first Gen name. She described those born between 1880 and 1900 as The Lost Generation, because they had lived a life largely lost to World War 1.

After World War 2, sociologists and demographers began to look backward, and the series of labels emerged: The Greatest Generation...