In Animal Farm, Orwell uses the various animals and people to represent actual people or groups of people from the Russian Revolution.
Boxer represents the working class. He is the backbone of the society but is abused. He is also fooled by Napoleon into being totally devoted.
Benjamin represents intellectuals who know things are wrong but don't care enough to do anything about it.
Mollie represents people who care only about material things and do not care at all about justice or freedom.
The dogs represent the secret police and others who provided the terror that helped keep Stalin in power.
George Orwell does a magnificent job representing many different groups of people in many societies, even though the backdrop for his characters is the Russian Revolution. It is interesting to see that these characters can also be seen today. For example, the dogs that protect Napoleon not only represent the secret police who protected Stalin in the early twentieth century, but are akin to any body guards used to protect any political figure or dictator today. What comes to mind currently are leaders of drug cartels who also have paid thugs to protect them.
Boxer can also represent the loyal and hard working laborers found in many nations today. They work for their own lives but also for their communities. They are also the backbone of any society because without them, the majority of the big projects wouldn't get done. Truckers and construction workers might come to mind when thinking about Boxer today; but during the Russian Revolution, they were the strong workers who were unwittingly manipulated by their own government.
Benjamin might represent professors, scholars, and intellectuals who know how the government exploits is people, but they choose to sit back and watch society ruin itself rather than do anything to help it. People like Benjamin must figure that it is safer to know and say nothing rather than get involved. They might also believe that society is too stupid to understand the complexities of what is happening around them that it is better to watch it disintegrate rather than take the time to teach others around them.
Mollie does represent those who are materialistic, but who also would rather seek after their own goals and aspirations rather than fight for what's right in their own communities. Mollie actually leaves Animal Farm in search of a different life because she didn't see that working under the pigs was what she wanted. Therefore, she might also represent capitalists or anyone else who left Russia for western countries in search of their own destinies. Rather than stay and help their home country overcome the suffering inflicted upon them, they chose to get out and seek their own fortunes elsewhere. This was difficult during Stalin's rule, however, because many were unable to leave Russia at all.