Robert Heinlein's The Moon is a Harsh Mistress is considered a sci-fi classic novel. It's a mostly deserved reputation for this tale about a revolution that overthrows Earth's Lunar Authority. The book has one of the finest depictions of the personality of an artificial intelligence. Said supercomputer is more than just a plot device that makes the insurrection possible, it is one of the best characters in the novel as we see it develop from its interactions with the protagonists who are the other leaders of the revolt. Another interesting characterization is of the inhabitants of the Moon, or Loonies. Their shared experience of penal exile to the barren, remote warrens of Earth's natural satellite is suitably reflected in their culture. Their language is a curious mix of neologisms and loanwords from other languages that sounds distantly futuristic even in the early 21st century (though of course, closer observation shows the dating of the novel: стиля́ги refers to a youth counterculture found in the Soviet Union of the 1960s). Their customs are believably developed in their unique situation: the concept of group marriage provides much needed stability for agrarian communities with a male-skewed sex ratio in a harsh, frontier world.
While most of the development of the Lunar revolt is plausible and built-up, here is where the novel shows its faults. For the first one, I'll be blunt: Heinlein sucks at writing military tactics. Seriously, Terran (1.0 g) soldiers losing in CQC to Loonie (0.17 g) children?! The former being defeated in firefights by the latter, who have barely seem firearms? The worst of this is at the beginning of the third part of the book, where Earth mounts an attack of Luna with troopships unsupported by artillery, armor, or air support. Did I mention the troops Earth used have no means of IFF on their pressure suits and they also haven't trained for combat in low-gravity environments? The outcome is predictable, Luna stronk. The revolution is better written when open combat is not involved. I have serious doubts whether I want to read Starship Troopers in the future, as I might just end up throwing the book in frustration.
The book spends quite a bit of time singing the praises of libertarianism. How different the author's views are from the characters is not clear. One character declares the most basic human right is to be able to trade in a free market. I would have though life would be the most basic right, but I suppose the ideal society treats it as a basic commodity. Lot of loving depictions (gratuitous even considering the societal circumstances) of young women, even girls, being married off to older men (note that this is listed under Author Appeal on TVTropes). Gold standard is best currency standard, which is then later contradicted by a quote about money "being a bugaboo of small men" (hard to expand the money supply when you need convertibility, Mr. Heinlein). Contract law is useless, reputation is enough. And taxation is not theft, taxation is WORSE than theft.
Being written in the 1960s, any weakness in the science can be excused by the book being decades old. Much is said about how cheap shipping goods from Luna to Earth is, apparently a gravity well that is like rolling stones down a hill. Someone else will have to comment on the plausibility of the catapult mass driver they use. It is curious that it is cost-effective to grow grain on the Moon and ship it to Earth. We are told Luna tunnel farming has massive yields but consumes much water and organic material. The novel is notable for being quite possibly one of the last mentions of Malthusian theory before the effects of the Green Revolution kicked into high gear.