Primarily it’s important to define the concept of oppression. Oppression implies to "any way in which humans as individuals or as groups, are treated with less than complete respect." (McCullough, p6). Many people engage in conversations that discuss various oppressions such as racism, sexism, heterosexism and classism, but rarely do we discuss how these oppressions interact with each other.
In the Combahee River Collective’s “Black Feminist Statements” the women write about the importance of identifying connections among various kinds of oppression; “The most general statement of our politics at the present time would be that we are actively committed to struggling against racial, sexual, heterosexual, and class oppression and see as our particular task the development of integrated analysis and practice based upon the fact that the major systems of oppression are interlocking.” Thus they suggest all systems of power are involved in the producing and reproducing of one another.
What makes this “interlocking” approach different from the way other feminist conceptualize oppression is that it does not start with gender and then add other oppressions such as race, class, sexual orientation, disability, etc but it connects them as one system, in which they are all dependent on one another. Thus instead of focusing on which system is more oppressed than the other it focuses on how they interact with various individuals in different situations.
“Replacing additive models of oppression with interlocking ones creates possibilities for new paradigms. The significance of seeing race, class, and gender as interlocking systems of oppression is that such an approach fosters a paradigmatic shift of thinking inclusively about other oppressions, such as age, sexual orientation, religion, and ethnicity.”(Charles C. Lemert)
Most individuals prefer to see their own victimization as the most major oppressions and value others as less important. Thus if each individual creates a major oppression, the result is a society with multiple systems of oppression that surrounds everyone’s lives. Thus for example in a system that we place African American women in the center analyzing, white women would be benefited by their race but punished by their gender. Thus an individual can be both oppressed or an oppressor depending on his situation in society.
Of course it's much easier to think of ourselves as oppressed than it is to think about the ways in which we are connected with the systems of oppression. For example,
My Iranian lesbian friend, who lives in Canada, has experienced sexist oppression in her family, in school and the whole community. However, she is also extremely wealthy and not disabled that means she has access to many advantages that many disabled and poor people are denied. She is not subject to racism as she lives in the multicultural and free country of Canada which gives her advantage among many lesbians who live in Iran.
while she is oppressed in certain ways, her identity is invest and perhaps even socially constructed, in relation to the systems which oppress people of color, disabled people and working-class people, or the ones who live in Iran, because she is benefitting from those systems of oppression in various ways. This does not mean her oppression is any less serious, than others but it means that she need to de-center her experience of oppression and stop seeing it as the most important.
When each individual in a society looks upon its oppression as a benefit in comparison with others that could be worst than what it is, that society would gain advantage because it only consist of one system of oppression instead of multiple major systems of oppression.

Dugald McCullough, “DISSECTING ‘-ISMS’”: explores the differences between oppression, discrimination and sectarianism, Vol.4, 1994, p 6
Charles C Lemert, “Social Theory: The Multicultural and Classical Reading”, 1998, P 555http://www.oppapers.com/essays/Oppression/180474

Oppression 9.1 of 10 on the basis of 3107 Review.