Here's why:
* Slang is as old as language itself. Every generation has its own ways of speaking, and that includes informal words and phrases. Even ancient cultures had their own versions of slang.
* Slang is fluid and dynamic. It's constantly changing and evolving, with new words and phrases appearing and disappearing over time. What's considered slang today might be common parlance tomorrow, or might fade away entirely.
* Slang is often tied to specific groups. It can be used by people in particular communities, professions, age groups, or even just close friends. This makes it hard to track its overall "popularity" as it's often localized and ephemeral.
What we *can* say is that slang has always played a role in language:
* It fosters a sense of community. Shared slang can create a sense of belonging and identity among those who use it.
* It reflects cultural trends and changes. Slang often reflects the interests, anxieties, and experiences of the time.
* It adds color and vibrancy to language. Slang can be playful, creative, and expressive, enriching the way we communicate.
Instead of trying to find a specific date for "slang's popularity," it's more accurate to view it as a natural and ongoing aspect of language that has existed for centuries, and will continue to exist and evolve for centuries to come.