Fundamentally memory exists as two components: long-term memory and short-term / working memory.

• The former stores information over long periods of time and is infinite, but has a long retrieval time. Here episodic memory enables humans to associate the solutions of previous problems with current problems. Routine tasks such as procedures and rules will also be learned here.
  
  
• Short-term/working memory is finite, but has faster processing times than long-term memory. This is fuelled from the senses and/or long-term memory for temporary demands on memory, i.e. less than one minute. Computing interfaces make heavy use of temporary information, and as such overburden or overload is easily achieved.
  
  
• Chunking is employed by the brain to combat overburden. Here information is grouped together so that it forms a single item to be recalled. Miller coined this in 1958 as the "magical 7 + 2." It would not be advisable to present the user with more items than this to remember at any given instance, lest overburden the one piece of PC hardware that can�t be upgraded - the player.