When the same information is presented in a different form that is easier to process, our ability to receive and remember it is greater. People often reorganize, regroup or compress information to aid in its understanding or recall. The resulting subgroups are ‘chunks’, which can be defined as a set of information or items that are treated collectively as a single unit (Mathy & Feldman, 2012). Chunking may be done through strategic reorganization based on familiarity, prior knowledge, proximity or other means to structure the information at hand. For example, a phone number may be split up into three subgroups of area code, prefix and number or one might recognize a meaningful date in it, and so can organize it more easily into different chunks.

In relation to the ideal amount of chunks, Miller (1956) found that humans best recall seven plus or minus two units when processing information. More recently, various studies have shown that chunking is, in fact, most effective when four to six chunks are created (Mathy & Feldman, 2012). Although this seems to be a ‘magic number’, it is also possible to learn to increase the size of those chunks over time (Sullivan, 2009).

In behavioral science, chunking has also been used to refer to breaking up processes or tasks into more manageable pieces (see for example Eşanu, 2019, on chunking in UX design or Wijland & Hansen, 2016, on mobile nudging in the banking sector).