Jordan Rich filled in on NightSide:

So, um, ah, like, you know, why do we speak the way we do today? I mean, literally! English 101 bans these “filler words” in our speech, but linguist Valerie Fridland says we should embrace our changing language as progress, not the collapse of civilization. In her book, Like, Literally, Dude: Arguing for the Good in Bad English, she outlines that language is both function and fashion. Fridland,a professor of linguistics in the English Department at the University of Nevada, Reno, joined Jordan to talk about the evolution of language!