Your working memory tops out at about seven items

In a landmark 1956 paper, Harvard psychologist George Miller pulled together decades of experiments and found a recurring limit: people can hold roughly seven, plus or minus two, items in short-term memory at once. Chunking information into meaningful groups is how we cheat past that ceiling.

— George A. Miller, The Magical Number Seven, Plus or Minus Two: Some Limits on Our Capacity for Processing Information — Psychological Review, vol. 63, 1956