Oscar Wilde called memory “the diary that we all carry with us.” His comparison of memory to a diary was intuitive because a diary is an organized store of specific information. Similarly, memory is defined as a composite of our stored representations of knowledge and the varied processes used to create and manipulate these representations. In the last two decades, there has been a revolution in our understanding of human memory. Human memory is no longer viewed as a unitary construct but as multidimensional and comprising several interrelated systems. Information about memory systems and how dementia affects them can be helpful to speech-language pathologists working with older adults.