This article seeks to define and explain autobiographical memory from a functional standpoint. For this, definitions are analyzed from cognitive and sociocultural perspectives highlighting how they converge in relation to components assumed as constituent of autobiographical memory and tasks attributed to it. A theoretical model about its functioning is reviewed and allows us to understand how the memory systems that constitute it interacting with process control and cultural patterns to generate autobiographical memories essential to maintain a consistent image of the individual and a moderately accurate record of the experiences. Its functions are described: self-definition, social interaction and self-regulation. It raises that autobiographical memories are multimodal, are distributed among memory systems and executive processes, and are mediated by sociocultural contexts