In terms of society, equality means the right of different groups of people to have similar social, economic, political positions and receive the same treatment. In other words, every person should get all rights which are enjoyed by others. But mankind is in the false impression about equality since its civilization started. Equality never possible, it is just a myth. Man built his society in such a manner where equality doesn't exist. There is no society in the world which enjoys the equality. Still men thrive for equality, which is, however, impossible until human society structure remains same.
Individual thinks either other person is greater or lesser to him but never equal to other. When civilization started this mentality influenced the structure of society and equality disappeared completely. Society is in different hierarchical structures, where persons at the top enjoy more benefits compared to the persons at low levels. Though this hierarchy is not rigid i.e. person position in the hierarchy changes according to the situation, group, time etc. However, there are always some persons who enjoy more benefits in the society than others. As the time passed, man started accepting the inequality in the society, perhaps he forgot equality. Men started ignoring the inequalities and gave different excuses to cover his acceptance to inequality. For example, every constitution tells about law of equality and simultaneously it tells about exemptions for that law of equality. Men accepted it. There may be different reasons for those exceptions, but all of them are just excuses to not to implement equality. Men cannot say there is equality when some other is above or below equal.
Men are used to inequality. They don't realize that the society where they are living is no equality zone. Equality is just theoretical, idle and abstract concept, which never exists in society. In simple words, Equality is an illusion.