This was a short, easy read. It's an allegory as to the human condition, I suppose. Basically, the animals on a farm rebel, throw out the farmer and decide to run the place themselves. At first, they work in community, agreeing that all are equal and all should have an equal say. Your basic theoretical Communist society. But then, a few of the animals, pigs in this case, take over bit by bit, begin putting on airs, begin providing extra privileges for themselves, and so forth.
While some read this as a condemnation of Communism, it's really broader than that. Any time people take unchecked power to themselves, they begin to exploit the rest of society. The lies, and brutality when necessary, that keep most of us under control exist just as much in so-called capitalist societies as in communist ones, in religious societies, even so-called Christian ones, as in secular societies. What's needed, of course, is a strong system of checks and balances, a system that is difficult to set up and difficult to maintain. Even in the U.S., which prides itself on such a system, it's been breaking down rather rapidly the past few years. Just lie unrelentingly until you get most people buying into a bogus "War on Terror", and you can take away all manner of privileges from the "lower classes" and extract all manner of extra costs from them. Yeah, even in the good old USofA, the pigs are putting themselves back in control. Who'd have ever believed the we'd find ourselves waxing nostalgic about the good old days when we had presidents with the moral integrity of Richard Nixon managing our futures?