Depth of Processing as a design principle promotes the effective recall of any piece of information that has been shown to a user as a consequence of a greater processing. A deeper process is related with three factors: distinctiveness of the information (how the information is different to previous experiences or stimuli), the relevance of the information (how the information is considered important or meaningful), and the degree to which the information is elaborated (a measure of cognitive effort required to process the information).
This principle can be related to the cognitive taxonomy proposed by B. Bloom: information pieces that just promote knowledge acquisition and comprehension are easily forgotten; while the ones that require more application and analysis (and other superior cognitive functions) are easily recalled.
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