Introduction of the paper "A New Conceptualization of Human Visual Sensory-Memory":

"The realization that human memory is not a unitary process but consists of multiple stores with distinct characteristics ledto the Atkinson–Shiffrin, or the “modal” model of human memory (Atkinson and Shiffrin, 1968). As shown in Figure 1, this model consists of three major stores: The input is first stored in sensory memory (SM), which exhibits a very large capacity, but can maintain information only for a few hundred milliseconds. A subset of the contents of this rapidly decaying memory is transferred to Short-Term Memory (STM; also known as Working Memory WM). STM is severely limited in capacity and can hold information for several seconds to minutes. Finally, information is stored in Long-Term Memory (LTM), a store with very large capacity, capable of holding information as long as one’s lifetime. Since its inception, the STM and LTM components of the modal model have undergone significant modifications (review: Baddeley, 2007), while SM has remained largely unchanged."

 A New Conceptualization of Human Visual Sensory-Memory (Ogmen et al.)