Why do cats meow

Cats  usually meow at people when they want something to do or to eat.So the vocalizations your cat makes are designed to get some attention from you and people around, or food, or playtime, whatever. Same thing goes for any kind of disturbance calculated to get your attention. 

Any kind of response other than ignoring your cat will actually reinforce the 
behavior. And your cat may feel uncomfortable.

The meow of your cat can mean many things. They can be demanding and very loud. Perhaps dinner is late, or their litter pan needs to be changed. 
Meow can also be in a soft way, sweet and affectionate, saying, "Thanks for being my friend or thanks for helping me with kindness". Tiny "meow" are the cat's way of manipulating the situation to get what they want. Most of us cannot ignore the little innocent "mew" that pleads with our emotions for a treat or petting sessions. 

Maybe she associates dinnertime with the most rewarding interaction with you. Spending some quality time with her, other than at dinnertime, might help curb this behavior. 

If your cat is upset, he will produce a variety of meowing calls that actually sound different from one another. These sounds convey different  emotions which are: 

• Anger 
• Fright 
• Pain 
• Attention 

ANGER 

This high intensive sound made by your cat when the cat is extremely angry and it is  called "caterwauling." The sound can vary but it is usually very high and extremely intense. 

FRIGHT 

 
If a cat is cornered and cannot run away or hide, it may make a 
throaty yowling noise. The cat may also spit and hiss. And usually tries to find a place to hide.

PAIN 

 
If your cat is in agonizing  he  will scream or screech according to the 
intensity of the pain. If he is a kitten, the sound will be that 
of a squeal. 

ATTENTION 

 
The sound that a cat owner will hear when his cat wants attention is a meowing noise. The meow can be of a begging or demanding nature in cats. 

Or the meow can be of a complaining or even an anxious kind of sound. The cat has refined its meow to such an  extent, that the cat owner knows by the way the meow sounds exactly what its feline companion is trying to convey.