I'd like to add a bit more about the characters.
Lena (Mama) Younger is the strength and soul of the family who must hold them together when it seems they are falling apart. Her dream is to have a house for her family.
Walter Younger is Mama's son and Ruth's husband. He feels he's treated as a child, and his mother and wife don't understand his dream to have his own business, especially when he wants to buy a liquor store.
Ruth Younger, Walter's wife, loves her family, but she is tired from the stresses caused by living in poverty. When she discovers she's pregnant, she considers having an abortion.
Beneatha Younger, Mama's daughter, is searching for her identity as an African American young woman in a white world. She dates one black man whose family is wealthy and has assimilated into society, and then she dates another man from Nigeria who encourages her to discover her African heritage.
Karl Lindner is a white man from the Neighborhood Welcoming Committee of Clybourne Park who visits the Youngers and offers them money not to move into their all-white neighborhood. When they don't take his money, he suggests that even though he isn't violent, violence could occur if the Youngers move.
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The plot revolves around the lives of the Younger family who are about to recieve a large check ($10,000) in life insurance money. The family's patriarch has just died. Each member of the family has ideas about how the money should be spent. The characters argue about the right way to do this, each believing their idea is the best.
The major conflict of Hansberry's play is the struggles of the African-American Younger family, who must battle against poverty and prejudice in mid-20th century South Side Chicago (approx. 1950). Though each family member's story, we learn how poverty and prejudice impacts their individual lives.
An example of dramatic irony can be found as Act I concludes. The protagonist, Ruth, is singing a song called "No Ways Tired" when in fact she is exhausted. She is also experiencing the fatigue that comes in the first trimester of pregnancy, which, of course, will lead to even more conflict.
The main characters are Ruth Younger, the pregnant daughter, who worries that her unborn child will just add more financial hardships to her already burdened family; Walter, the male protagonist, who wants to invest the money in a liquor store, and Beneathea, who dreams of becoming a doctor.