The Baddely and Hitch model of working memory is composed of four components:

– The central executive, which acts as supervisory system and controls the flow of information to and from its slave systems.

– The phonological loop, which deals with sound or phonological information; any auditory verbal information is assumed to enter automatically into the phonological store.

– The visuo-spatial sketchpad, which holds information about what we see; it is used in the temporary storage and manipulation of spatial and visual information, such as remembering shapes and colors, or the location of objects in space. It is also involved in tasks which involve planning of spatial movements, such as planning one’s way through a complex building

– The episodic buffer, which is a third slave system, and is dedicated to linking information across domains to form integrated units of visual, spatial, and verbal information with time sequencing or chronological ordering, such as the memory of a story or a movie scene.