My Cat Has Developed Bald Spots. What Does This Mean?

Sometimes cats can develop bald spots as a result of over grooming. This may be due to stress. Often if there is a new baby in the home, new person living there, or even a new cat or dog, the cat will resort to comforting itself and it may groom itself as a means of comfort. When it does this repeatedly it will actually leave bald spots, so think about anything which has changed in your household which may be causing the cat stress.
It could however, be a dermatological condition, caused by a variety of factors. Sometimes the vet may prescribe some cream, or s/he could look at steroids to help the condition.
For this reason it is always important to have a cat which has bald spots examined by a vet to ascertain if it is a medical or psychological condition, since the position and nature of the spots will be looked at by the vet and appropriate treatment recommended.

Does your cat wear a collar, this may be irritating her, also, if she goes outside, she might have gotten a tick and scratched that area, I would check if there is a bit mark, if there is a tick or flea in there, you can use olive oil to extract it

Could also be a ruptured abscess from a cat fight. If bald patch is on the back of the neck, did you recently apply Frontline or Revolution to that area? Some cats can have a minor reaction and hairloss from these products. Regardless, a trip to your vet is best if you have any concerns.

There can be any number of reasons for this. Ringworm, allergies, maybe even stress. I think you should take the kitty in to the vet to find out why. Hope this helps, good luck to you and the kitty.