Step 1 : Introduction to the question " Which animal meows? "
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A meow is a vocalization of cats. They might have diverse tones and are sometimes chattered, murmured or whispered. Adult cats rarely meow to each other, so an adult cat meowing to human beings is probably a post-domestication extension of meowing by kittens; a call for attention.
The meow can be assertive, plaintive, friendly, bold, welcoming, attention-soliciting, demanding, or complaining. It can even be silent, where the cat opens its mouth but does not vocalize. Just as humans may verbalize exhaustively when they are happy, so can cats. According to The Purrington Post, a chatty cat is likely happy too.
More Info:
en.m.wikipedia.org