Valentino Achak Deng is a South Sudanese author and humanitarian known for his memoir, "What Is the What." The book recounts his experiences as one of the Lost Boys of Sudan, a group of children who fled their war-torn country during the Second Sudanese Civil War. Deng's story highlights the struggles of displacement, survival, and the search for a new home. In addition to his writing, Deng is actively involved in humanitarian efforts, particularly in education and support for refugees. He co-founded the Valentino Achak Deng Foundation, which aims to improve educational opportunities in South Sudan and assist those affected by conflict.