Savant syndrome is one of the most fascinating phenomena in the study of human differences and cognitive psychology. An individual with savant syndrome is one who has been identified with a rare condition, mental disabilities, or certain disorders, including autism spectrum disorder, and who has one or more areas of extraordinary ability or brilliance, in stark contrast to serious individual general limitations. Their skills emerge spontaneously; they are literal, not symbolic; and they are not derived from practice. Savants have no idea of how they possess these skills. Their condition may be genetic, but may also be acquired in the pre-natal, perinatal, or postnatal stages. There are also cases in which savant syndrome is acquired later in life, following a blow to the head, a stroke, a central nervous system injury, or disease.The most dramatic examples of savant syndrome occur in individuals with exceptional skills in certain areas who simultaneously score very low on intelligence quotient tests. It is paradoxical that individuals with a low intelligence quotient can perform extremely complex mathematical calculations that, in most cases, only individuals with a high IQ can perform. They may pose a challenge to many theories of intelligence, since their performance cannot be understood in terms of conventional intelligence. Individuals with savant syndrome have a prodigious memory and spatial visualization abilities, are attracted to numbers and calendars, and are generally fascinated by music and art. Other skills, such as polyglottism, occur less frequently. The most common kind of savants are calendrical savants, also known as "human calendars," who can calculate the day of the week for any given date with remarkable speed and accuracy. It is disputed whether calculation, rather than memory alone, is involved. Half of savants are autistic, while the other half has mental retardation, CNS injury or disease, or other types of disorders such as Williams' syndrome, Smith-Magenis syndrome, Prader-Willis syndrome, loss of corpus callosum, etc. On the other hand, approximately one in ten autistic people (10%) show savant abilities. Savant syndrome is also approximately six times more frequent in men than in women. Hill (1978) calculated that of 105 individuals classified as savant in 63 publications, at least 85% were men. One of the more plausible explanations for savant syndrome is associated with a dysfunction of the left hemisphere of the brain, whose skills are more abstract, logical, and symbolic, while the right hemisphere is used to compensate, leading to a cortical reorganization. There are many hypotheses associated with understanding more about the Savant syndrome, but none of them are completely sufficient. This is a very heterogeneous area of research historically dominated by anecdotal reports. Additionally, since each savant has their own peculiarities, most reviews take the shape of a collection of stand-alone descriptions. As Ammari (2011) has stated, "there is a lack of unifying definitions, diagnostic tools, age categories, and spectrum of prodigy all of which might be regarded as a disadvantage to savant syndrome." Considering all these factors, the purpose of the present essay is to analyze the different cases more rigorously, considering mainly persons with severe intellectual impairment who can perform in sharply circumscribed areas at a remarkable high level. This is the first time that so many profiles have been brought together in a single paper or book. Twenty-nine of these savants are men and seven are women. Twenty-four of them are from the United States, six are from England, and one each is from Scotland, Italy, Turkey, the Philippines, Taiwan, and Malaysia. Seven of the people profiled here are acquired savants whose abilities emerged after a CNS injury or disease.