HeLa cells are a type of human cell line that was derived from the cervical cancer cells of Henrietta Lacks in 1951. These cells were the first immortal human cell line, meaning they can divide indefinitely in a laboratory setting. HeLa cells have been crucial for medical research, contributing to advancements in cancer treatment, vaccine development, and understanding various diseases. The unique properties of HeLa cells allow scientists to conduct experiments that would be difficult or impossible with other cell types. They have been used in numerous studies, including the development of the polio vaccine and research on HIV/AIDS. Their widespread use has raised ethical questions about consent and the use of human tissues in research.