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Question of the day Pets & Animals

Why Do Cats Purr? What the Sound Can Tell You

Short answer

Cats purr to communicate and regulate their state

Cats purr in familiar social situations, such as when they feel comfortable or seek contact, but purring can also occur during stress, discomfort, or illness. The sound is a form of communication, not a reliable sign of happiness by itself.

Main role
Communication in different situations
How it sounds
Repeated low-frequency vibration
Important clue
Read the whole body

Read the full answer 6 min read · Further reading: American Veterinary Medical Association

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Start here

Twelve good first questions, each with its short answer.

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  1. One real questionEach page takes one question people type into search, such as why the sky is blue or how long to boil an egg.
  2. The short answer firstA one-line answer, a two-sentence explanation and three key facts sit at the top, before any detail.
  3. Where to read moreEvery answer names the organisation that covers the topic, such as USDA FoodSafety.gov, NASA, the National Weather Service or Merriam-Webster.