why cats purr?

Hi, the way I always understood is that cats purr because they are happy and content and not tense. I have seen my own cat tense and he was not purring but hissing,swatting ,growling and had his back arched like he was geting ready to attack.That's a new one...cats purring because they are tense...not likely.

Hi there Jimmy Sun. In most cases they purr for themselves rather than to please us - the reasons may consist of fear as they try to relax them self with purring, or when they are happy (that's when you actually pet them and they start purring all of a sudden).

Well I cant say exactly why but Iv read in a cat magazine that cats have been known to purr for more then one reason they purr when there happy and in some cases they purr when in distress I read that there are many reasons that cats purr.

I don't think it's really known exactly WHY cats purr, but I do know they start to purr when they are being pet and as they start to relax and also when they eat

My cats shocked when their don't know what their see, they always happy and learn about something strange. I don't know what must i say ....