There is only so much our short term memory can retain - hence the importance of writing things down. Some have suggested the magic number 7 as our brain’s capacity to store things for immediate retrieval (short-term memory). Indeed, Atkinson-Shiffrin came up with their "three store" memory model: a sensory register, short-term memory (STM) and long-term memory (LTM). According to this model, STM has a duration of 15-30 seconds and a capacity of roughly 5-7 items. So, given t