**1. Introduction**

The term "ataxia" or also "distaxia" means the inability to coordinate, but at the same time, it is also used to describe the group of underlying neurological disorders that affect coordination, balance, and speech. The delineation of ataxic disorders as distinct entities can be said to have begun with the description of siblings with ataxia by Nicholas Friedreich in the 1860s, suggesting a genetic etiology, though there are possible descriptions of similar disorders antedating this [1–3].

Ataxic disorders also refer to symptoms that affect the coordination of these movements. They may be a symptom of several degenerative medical or neurological conditions of the nervous system that compromise the movements of different regions of the body — fingers, hands, arms, legs, eyes, balance, muscle tone, swallowing, and speech. It can also be manifested as a lack of coordination that impairs voluntary movement as a whole. The common symptoms of ataxia are similar to those of a drunk such as slurred speech, stumbling, falling, and incoordination [4, 5].

The number of ataxia subtypes is unknown, but it is estimated that there are at least 100 different subtypes, each with a distinct etiology. To date, current classifications subdivide ataxias into three large groups: (i) degenerative ataxias, (ii) hereditary ataxias, and (iii) acquired ataxias related to exogenous or endogenous non-genetic insults [5].

The purpose of this chapter is to provide a brief introduction for academics and clinicians with introductory tips for understanding, evaluating, and managing ataxias in general.
