I enjoy many books, but it seems like it's the Sci-Fi / Fantasy ones that really make me think. And one of the great things about reading is that you always have something to think about when you're not reading. So here are some of my favorite authors in this genre in alphabetical order:
1. Isaac Asimov
He has been around forever and was one prolific writer. In fact, he was probably my introduction to this genre. I especially liked his Foundation series and his short story, Nightfall. I think one of the main things his writing did was make science fiction accessible to everyone because they were as much about people as about science.
2. Octavia Butler
She has several books, but the only ones I've read are two of a trilogy, Dawn: Xenogenesis and Adult Rites: Xenogenesis. I believe the third one is just called Xenogenesis, but I haven't read that one yet. Dawn starts with a woman waking up on what she finally understands is an alien ship, and she has been on it for decades. Earth has been destroyed by war, and these aliens have plucked a few hundred survivors from the ruins. The book mostly deals with how she learns to relate to these new captors? protectors? villains? friends? The whole thing is fascinating, especially as you learn about a completely strange alien culture.
3. Mercedes Lackey
She is probably my favorite author in this genre. In fact, I'm reading one of hers right now, and I keep thinking, I'm SO enjoying this! She has several series and I've read some in three of them. The first series is called THE VALDEMAR UNIVERSE. There are several sub series within the group and I read the first two of the THE COLLEGIUM CHRONICLES sub series. I liked the first book, Foundation, a lot, but the second, Intrigues, not so much, so I may not continue that group. I do plan, however, to explore the other series about Valdemar.
The next series I enjoy is her Elemental Masters. I've read The Wizard of London, Reserved for the Cat, and Home from the Sea, all very good. I do plan to read all the books in this series.
But my absolute favorite series is her Tales of the 500 Kingdoms. Right now I'm reading the last one and, like I said, thoroughly liking it. These stories are generally about the fairy tales we all know, but with several twists. For example, my current book is Beauty and the Werewolf. The first one I read, not the first in the series, was One Good Knight and it was very funny.
4. Ursula K. Le Guin
She is the grande old dame of science fiction. She's been around for a long time and probably has about a million books. I've only read two, however, and they are amazing. First was The Left Hand of Darkness and the other was a sequel, Four Paths to Forgiveness. Again, they are about an alien culture, this one with slavery, and what happens to both the slaves and their owners. They are smallish books, around 200 pages, but they are dense, and it took me some time to read them. It was well worth the effort.
5. Terry Prachett
Prachett is absolutely hilarious! The New York Times calls him, "the purely funniest English writer since Wodehouse." He writes about a weird place called "Discworld," which is a flat planet on the backs of large turtles. I've read three of his: Equal Rites, Snuff, and Going Postal, which I heard as an audio book while driving. There were several times I was laughing out loud at stop signs and people must have wondered about my sanity. He also wrote another one (not about Discworld) with Neil Gaiman called Good Omens: the nice and accurate prophecies of Agnes Nutter, witch. This was the first one I read and was a good introduction to his hilarious and nonsensical style.
6. Star Trek Novels
I have also read many (many, many) Star Trek novels, but their quality is spotty at best and most of them are pretty forgettable. My favorites, however, are excellent and they are Ishmael by Barbara Hambly, Yesterday's Son and Time for Yesterday (two books about Spock's son) by A.C. Crispin and probably my absolute favorites, and two about Romulans: My Enemy, My Ally and The Romulan Way.
And there you have it. Enjoy going to other worlds.