Robert A. Heinlein is the third, and most important, of the three novas to hit the SF field. He appeared in 1939 with the publication of his story "Lifeline". In 1941 he was guest of honor at the World Science Fiction Convention in Denver. In essentially zero time, he went from being unpublished to being the dominant writer in the field. Nobody else will ever be this important in the field again, because there's now just too much of the field around for any one person to dominate the way Heinlein did.
Heinlein is one of my most important, and most re-read, authors.
I do regret many of his later books, especially The Number of the Beast and The Cat Who Walked Through Walls. But even his bad books are very readable.
I've written notes on books I've read, including a number of Heinlein novels
See them all here .
It's the usual way to refer to them, but it's not very accurate. They do tend to feature young-adult protagonists, and they do tend have coming-of-age themes, and they don't have sex (beyond occasional raising of John Thomases).
The Rolling Stones
A special favorite of mine. The Unheavenly Twins take on the universe, mostly by talking fast. Also has a semi-connection to The Moon is a Harsh Mistress, though Hazel Meade Stone—though it's not consistent in several ways.
Have Spacesuit, Will Travel
Even when I first read this, in the '60s, it was dated in some ways. The small town life, soda fountain jobs, and such, weren't part of my experience (I lived in a small town, but it was a small college town during the '60s). However, the desperate drive of the protagonist to get into space was something I could connect with. I didn't feel it directly myself, but I was interested.
So, when he won a consolation prize in the contest that should have taken him into space, and ended up with a used spacesuit instead, I sympathized. I liked his idea of fixing it up; I wasn't a mechanic type myself, but I liked the idea. I wasn't particularly good with manual skills; not a good woodworker or draftsman or artist or whatever. But I admired those who could do that stuff, I didn't look down on them. At least those who could do it well, and understood what they were doing—like Heinlein's characters. I also admired the good theorists, and probably thought that was where I would end up (though I wimped out into computer work instead), but I didn't think it was the only valid path.
And then, of course, while he was testing the fully rebuilt suit, he got picked up by an alien ship and ended up on Pluto, and then in another star system, where he had to argue in court for humanity's right to live. Pretty strong stuff.
This is one of the novels that's been reissued in an author's preferred edition (the others are The Puppet Masters and Stranger in a Strange Land). In this one, it's a modest improvement. There's a bit more political philosophy, but not enough to bog it down, and the polishing isn't badly disturbed.
The Moon Is A Harsh Mistress
His greatest work. One of the greatest SF novels ever. Hugo winner.
This was actually written, originally, to be a juvenile. Hugo winner.
Stranger in a Strange Land
His most famous book, I think. Not his best, I think, but interesting. Jubal Harshaw is quite a character.
It's sad that in a book where he allegedly set out to reverse all the popular notions of good and bad, and where he certainly gave favorable treatment to many unpopular ideas (cannibalism, polyamory, an afterlife, vigilante capital punishment) he still managed to come out against homosexuality. (But he got better later).
Air cars are a great story idea, but I just don't think we're going to see them anytime soon.
This book seems to me to show some of the beginnings of the decline that much of his later work displayed—excessive interest in sex, especially sex with much younger women; less connected stories; more philosophical preaching. Mind you, I like Heinlein's philosophical thoughts, but he seemed to me to convey them better in earlier books.