Some general chicken terminology
The chicken (Gallus gallus domesticus) is a domesticated fowl, a subspecies of the red junglefowl
Newly hatched chickens are called chicks
Male chickens less than a year old are cockerels
Adult males are known as cocks the UK and Ireland. In North America, and Australia they are more commonly called roosters
A cockerel that has been castrated to improve the quality of its flesh for food is known as a capon
Young females are known as pullets
A pullet becomes a hen when she begins to lay eggs at around 19 to 21 weeks old
The best age to get your chickens is at point of lay or POL (16-20 weeks depending on breed and season) when you can be certain they are hens rather than cockerels, no special care or diet is required, and they are also still young enough to tame
The parts of a chicken