Sometimes I forget that not everyone is as obsessed with books as me and thus I might use some terms or abbreviations that while quite common in the bookish community, are not familiar to everyone else.
DNF-did not finish. Life is too short for bad books, so many books, so little time, it pains us, but sometimes you just have to admit that you're never going to finish it.
OTP-one true paring. Not always having to do with books, but always having to do with fandoms, this is the couple you're rooting for against all odds, and sometimes, even against the author's intent.
TBR-to be read. Sometimes a literal list on Goodreads, sometimes a stack on your bedside table, sometimes a full shelf in your bookcase, no matter what, always growing.
YA-young adult. Books technically geared towards young adult or high schooler readers, but widely read by people of all ages, think The Hunger Games by Suzanne Collins, Twilight by Stephenie Meyer (shut up, you know you read it), or Fangirl by Rainbow Rowell.