Mnemonics are memory aids that improve encoding and retrieval, often by using vivid imagery, organization, or familiar structures. They turn arbitrary information into something more memorable.

Classic techniques include the method of loci, in which items are imagined along a familiar route, and the peg-word system, in which items are linked to a pre-memorized set of pegs. Acronyms and acrostics compress lists into single words or sentences. Rhymes and songs exploit the power of rhythm and melody. Medical students, actors, and competitive memorizers rely heavily on such devices.

Mnemonics work by providing retrieval cues and by encouraging elaborative encoding. The more distinctive and interactive the image or structure, the more effective the aid. They do not increase the underlying capacity of memory so much as they make better use of the capacity that exists. With practice, the creation of mnemonic links becomes rapid and nearly automatic.

When the material itself is dry or unordered, a mnemonic supplies the structure that memory prefers.