Rett Syndrome is a rare genetic disorder that affects brain function and development. The disorder is also known by other terms such as Rett's Disorder, Rett's Syndrome, and Cerebroatrophic Hyperammonemia. It was first described in 1966 by Austrian physician Andreas Rett. The disorder is characterized by developmental regression, loss of speech, functional hand use, and mobility, as well as breathing problems, seizures, and a range of other medical issues. However, while these conditions share many symptoms, there is only one specific term used to describe them- Rett Syndrome. No matter the term used, all those with the disorder require personalized care, and families with a child with Rett Syndrome should seek support from health care providers and support groups to help navigate this challenging condition.