There is a lot to breeding chickens, which includes determining the breeds by the similarities between the chickens, in terms of colour, feathers and various other factors. Usually breeders keep birds of the same breed together in order to not end up with chicks, that each looks different from one another. Not to say breeders never do that!
The more experienced and professional breeders, who are forever looking for new breeds of birds, do experiment and the numerous colourful and beautiful birds out there are a result of such experimentation.

Breeders venture into breeding chickens for a variety of reasons. Some breed chickens for the purpose of getting eggs and some use them for exhibiting and others for meat production.

Breeding differs depending on the goal of the breeder. The traits of the chickens are taken into consideration.

If a breeder is looking at breeding solely with the aim of laying eggs, he looks for the trait of "fecundity", which is the ability to lay eggs. Egg laying chickens are much smaller in size, as their food intake is less and directed towards creating eggs and not body mass. These egg laying chickens are further categorized into two groups depending on the colour of the shell, white shelled eggs or brown shelled eggs. Chickens that eat more or those that brood are said to be unfit for laying eggs.

Breeding for the purpose of exhibiting the chickens requires totally different traits, such as good looks and plumage color. Chickens that have feathers on their feet are not fit for exhibiting. Basically, a healthy and good looking chicken is what they look for.

Those looking to breed chickens for their meat, look for particular traits in the chickens. Chicken varieties that have the capability to grow larger and faster and birds that are most efficient at converting their feed to meat are best suited. Their food intake is solely for the purpose of increasing the flesh and hence these chickens do not lay as many eggs as the egg laying variety. Another trait breeders look for is their resistance to infection.

A person interested in breeding, should select the characteristics that are most important for the purpose the chickens are intended. There are several breeds of birds and each type is genetically developed in order to satisfy the requirement.