A review of recent large-scale studies on gender differences in processing speed and on the cognitive factors assumed to affect processing speed was performed. It was found that females have an advantage in processing speed tasks involving digits and alphabets as well as in rapid naming tasks while males are faster on reaction time tests and finger tapping. Females also outperform males in reading and writing skills. However, no significant gender differences were found in general, crystallized (verbal) or fluid (nonverbal) intelligence, nor in the more narrow skills measured by individual subtests of common IQ tests, nor in short-term memory or inspection time. It is concluded that gender differences in reading and writing fluency may have a significant effect on gender differences in processing speed tasks. Following Lynn and Mikk (2009), it is suggested that female superiority in reading and writing skills may be partly based on their deeper engagement in language related activities at school and at home. Male superiority in reaction time and finger tapping tests is most likely based on other factors. The results of the study support the theory of several speed abilities as opposed to a general processing speed ability. (Contains 1 table.)