Figure 3 shows a representative information processing model. I-P theory postulates that there are three memory systems: sensory memory, short term (or working) memory, and long-term memory. The human mind takes in information from the environment (it attends or focuses), performs operations to change the form and content of the information (it organizes the information in some logical way), and stores the information in the long-term memory so that it can later be retrieved when it is needed.