I read cozy and historical mysteries, a bit of Paranormal/UF, and to mix it up, I read science and gardening books on occasion.
Since non-fiction has been put on the table, I'm including my supplemental list of non-fiction books that I think are ... somewhat essential. This one is harder, because, up front, I'm not an academic, and I have a low tolerance for edifying reads, if they are dry or boring. So I went into this list asking myself what books have I read cover topics that I think are essential to developing a better understanding of the world. This is what I came up with:
The Invention of Nature: The Adventures of Alexander von Humboldt, the Lost Hero of Science by Andrea Wulf: This is the one essential book on this list. Everyone should read this at some point in their life. That Humboldt has become lost in the mists of history is a travesty, as he truly was a genius who recognised two centuries ago what we're just figuring out now.
Quiet: The Power of Introverts in a World That Can't Stop Talking by Susan Cain: With diversity getting so much attention these days, I think it's important for everyone to understand what is arguably a fundamental level of difference; introversion transcends gender, race, and religion, and offers critical advantages to humanity's progress and neigh, survival.
Headstrong: 52 Women Who Changed Science-and the World by Rachel Swaby: Because it's essential to know that women have been getting it done and changing the world for far longer than history would like you to believe.
Rain: A Natural and Cultural History by Cynthia Barnett: because climate change isn't going to go away if we pretend it's not there, and as Noah found out millennia ago, water (or the lack of it) is nothing to sneeze at.
The Genius of Birds by Jennifer Ackerman: We are an arrogant species and the world would be better off all around if we only knew and acknowledged that we are not necessarily the smartest species simply because we are the ultimate apex predator.
The Elements of Eloquence: How to Turn the Perfect English Phrase by Mark Forsyth: In the era of social media, it would be refreshing if only those that spoke the loudest had any clue as to how to speak the most eloquently - or hell, even coherently.
The Book: A Cover-to-Cover Exploration of the Most Powerful Object of Our Time by Keith Houston: We, as book lovers, might appreciate an understanding of the book's history. If so, this is an excellent and comprehensive history.
A Short History of Nearly Everything by Bill Bryson: Just think for a moment: even lacking as it is of any depth, imagine that every student had to read this book. Now imagine how much smarter and better informed registered voters everywhere would be. Baby steps are better than no steps.
Jambusters: The Story of the Women's Institute in the Second World War by Julie Summers and The Candy Bombers: The Untold Story of the Berlin Airlift and America's Finest Hour by Andrei Cherny: Creative problem solving is a perennially useful skill but never more so in times of greatest adversity - like war. Learning how humanity gets into the messes it does is crucial, but so is learning how people get through those same messes. Also, I'd argue that there's a larger message about sugar being a catalyst for peace, but I won't insist upon it.
Dawn of the Belle Epoque: The Paris of Monet, Zola, Bernhardt, Eiffel, Debussy, Clemenceau, and Their Friends and Twilight of the Belle Epoque: The Paris of Picasso, Stravinsky, Proust, Renault, Marie Curie, Gertrude Stein, and Their Friends Through the Great War by Mary McAuliffe: Both of these books are an excellent way to 'side load' history into reluctant students of history. Well written and incredibly informative not only about the artists the books purport to be about, but about the events in history that shaped them.
At the Existentialist Café: Freedom, Being, and Apricot Cocktails by Sarah Bakewell: Philosophy is non-negotiable for any critical thinker, but like anything that is essential, it's hard. Sarah Bakewell has done the impossible here: she's not only made existentialism understandable, but she's made it fascinating. Ok, I lied above when I said there was only one book on this list I considered essential in and of itself. This one is too. Everybody should read this book.