(1) Learn the corresponding code, keep the corresponding storage, and identify (recall) the corresponding retrieval. But strictly speaking, memorization is the result of coding, retention is the result of storage, and recognition (memory) should be the result of extraction.

(2) Transient memory lasts for a few seconds, short-term memory lasts less than one minute, and long-term memory lasts more than one minute. This is a principled division standard, which is difficult to be strictly divided in practice.