What does it mean all animals are equal but some animals are more equal than others?

A proclamation by the pigs who control the government in the novel, Animal Farm. The commandment which originally stated: "All animals are Equal", is changed by the ending, when the pigs have officially taken command in unequal ways. The last chapters of the novel show how corrupt the farm has turned, as the pigs are given more privileges than any other animal. By the time the pigs are seen as supreme, they gain a strong resemblance to the humans who had once ruled them.