: This is also known as Permanent Memory. Here the individual learns and retains the information fora very long period of time. There is an interval of time between learning & recall or reproduction. Thus permanent memory is involved e.g. knowing our account number of the bank or the phone number. So we see that memory is a process involving learning & reproduction. The amount of material that can be immediately reproduced after one repetition is called span of memory. The phenomenon of memory maybe studied under four different aspects viz.the four Rs.