|Memory: Short Term Memory|
Short-term memory describes items that are remembered for a short period of time (up to a couple of minutes). There is also a type of memory called primary or iconic memory, which stores direct sensory impressions.
Short-term memory is usually investigated using simple items that only need to be remembered for a short period of time. Iconic memory is usually investigated with letters, numbers, or symbols, presented for around 50 milliseconds per display.
The classic measure of the capacity of Short Term Memory is 7, plus or minus 2, which was first proposed by Miller and has held up well since. One can remember approximately 7 chunks of information at a time, where a chunk can be a number, letter, word, phrase, or any other piece of information that is remembered as a unit.