A detailed understanding of reactive intermediates is at the heart of chemical transformations, and thus of modern organic synthetic chemistry. Carbocations are electron deficient species that are the most important intermediates in organic chemistry. This comprehensive review gives practical information on the synthesis, mechanisms, and spectral studies related to carbocation chemistry A detailed reference for all aspects of charbocation chemistry. With numerous classical examples of studies of carbocations to serve as illustrative principles in organic and physical organic chemistry. Provides insight into future developments in the field and practical applications.