Neural folds are structures that form during the early stages of embryonic development in vertebrates. They arise from the neural plate, which is a flat layer of cells that eventually folds to create the neural tube, a critical precursor to the central nervous system, including the brain and spinal cord. As the neural folds elevate and converge, they eventually fuse at the midline, completing the formation of the neural tube. This process is essential for proper development, and any disruptions can lead to neural tube defects, such as spina bifida or anencephaly.