Purring is a form of cat communication and is often apparent when a cat is happy and content. Cat owners love it when their cat purrs.
Some cats purr when they are threatened or in danger.
Strangely enough, scientists haven't yet found out what exactly makes the purring noise. Some believe that the cat is moving muscles quickly that control their 'voice box' to purr, but there is no proof! So we don't really know how cats purr.
Often, mother cats purr when they are near their young, and the young purr back to their mother. A queen will normally purr when giving birth!
Purring can be of different pitches and loudness - all cats purr slightly differently!
Rabbits can also purr, as you can find out on our rabbit facts page!
This week's Pet Of The Week is Humphrey, submitted by Christine. This photo of Humphrey has now appeared on this website 32716 times!
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