Another moral in Animal Farm is that media and communication are powerful tools, and it is possible to influence public opinion through them. It is important that we take everything that the media tells us with at least a grain of salt, because as you can see through the portrayal of Squealer, the media is easily used as a tool of propaganda. If propaganda is not challenged, and it is believed, the the ruler will just have that much more control over you.
A third moral in Animal Farm is more of a reminder. It is not as hard as one would think to fall into the trap of communism. Throughout this book, you can see how the little choices made that don't seem so bad at the time end up resulting in a bad end for the animals.
In this novella, one can look at the various characters and see who they are portraying in real life. For instance, Farmer Jones is the Tsarist Regime; lazy, ill tempered, and leading the farm into ruin. Old Major is Lenin; the bringer of the original ideas and philosophies who left before the revolution came to fruition. Snowball is Leo Trotsky; having big plans for the farm (Russia), but ultimately banished by his political enemy before they could come into effect. Napoleon is Joseph Stalin; an iron clad leader, extremely paranoid about losing power, who put into place some improvements but ultimately did not benefit the citizens of the farm or Russia. Boxer represents the ideal working class people who believe that their leader is always right, and that they must always work harder. Mollie represents the middle class people, life wasn't so bad for them under the Tsar and they fled soon after the revolution to a happier life for them; never to be talked about among the animals or Russians again. Squealer represents the media of Russia, used as a propaganda machine by Stalin (Napoleon).
Thus, in my opinion, the main purpose of this book was to satirize the communist government of Joseph Stalin and the events that led to his government. I also think that it demonstrates that even when one believes that the leaders are the most intelligent and best suited to the task, and believe that they will rule in favour of all, power always corrupts, and absolute power always corrupts absolutely.