I grew up in the '70s. Things were so different back then. Bad hair wasn't a day, it was a way of life. Words were different back then too. Fortunately, social media has permanently hijacked some of those words and given them a completely different meaning.
For me, slang is at the social interface of language. Slang words aren't linguistically different from other words, except that they keep on moving. It is my considered opinion that slang is a bag of snakes.
With uncanny adroitness, my husband and I bantered in perfect 2012 lingo. And with no Gen Xers or millennials in the vicinity to ridicule my retro-linguistics, I'll tell you (and don't tell the children), it was a totally tubular moment.