Daniel Tammet is a British author and savant known for his exceptional mathematical abilities and unique cognitive skills. Born on January 31, 1979, he has a rare condition called savant syndrome, which allows him to perform complex calculations and memorize large numbers with ease. Tammet gained fame for his ability to recite the number π (pi) to over 22,000 decimal places in just under five hours. He has written several books, including Born on a Blue Day, which details his experiences living with autism and synesthesia, a condition that causes him to perceive numbers as colors and shapes.