The three steps of memory information processing are encoding, storage and retrieval. This information comes from the senses and takes many different forms such as images, sounds and meaning.
The brain encodes information through visual coding, acoustic coding and semantic coding. It may use more than one type, such as seeing a word (visual coding) and thinking of the word's meaning (semantic coding). Short-term memory can hold five to nine items, but the brain can hold more if it combines information into chunks. Long-term memory does not seem to have a limit. The brain retrieves information from short-term memory in sequential order, but it retrieves information from long-term memory by means of association.