Miller's Law
The average person can only keep 7 (plus or minus 2) items in their working memory.
Key Takeaways
Don't use the "magical number seven" to justify unnecessary design limitations — the number is about chunks of information, not a strict UI rule.
Organize content into smaller chunks to help users process, understand, and remember information more effectively.
Remember that short-term memory capacity varies among individuals based on their prior knowledge, context, and the nature of the information.
Origin
In 1956, cognitive psychologist George Miller published one of the most highly cited papers in psychology, proposing that the span of immediate memory and absolute judgment were both limited to around 7 pieces of information. His work centered on the concept of "channel capacity" — the threshold beyond which confusion leads to increasingly inaccurate judgment. Miller's insight was that chunking information into meaningful groups could effectively extend the practical limits of working memory.