Amyotrophic Lateral Sclerosis (ALS), also known as Lou Gehrig's disease, is a progressive neurodegenerative disorder that affects nerve cells in the brain and spinal cord. It belongs to a group of conditions known as motor neuron diseases. ALS gradually leads to the degeneration and death of motor neurons, which are responsible for controlling voluntary muscle movements. As the disease progresses, individuals may experience muscle weakness, paralysis, and difficulties in speaking, swallowing, and breathing.