In English and, presumably, many of the world's other commonly spoken languages, there exists a rough category of words considered slang. This concept is not quite the same as taboo (many slang words are not really related to taboo topics), colloquial language (I think that a number of colloquial lexical items, like "yeah," could not be reasonably classified as slang), new/youth words (COVID is obviously not slang; on the other hand, some slang terms are quite old).
I feel that standardized writing plays a role in the concept. Slang words are ones which are significantly less common in formal writing than in everyday speech. However, this also applies to non-slang colloquial words and linguistic features.
Formal education also seems to play a role. Educators use colloquial words and newer features of their language often (One of my teachers said "your guys's" at least half a dozen times when explaining the instructions for the SAT), but they are unlikely to utilize slang terms very much. Speakers learn these words in other places.
Because of these factors, I am wondering whether a concept of "slang words" exists in cultures whose languages don't have significant written traditions and aren't taught in any formal education system. Do such cultures recognize certain words as slang? Is the concept as prominent in these cultures as it is in the Anglosphere?