The word "feral" is used to define a cat that lives outdoors and it essentially does not belong to anyone.
Feral cats are the result of a domestic cat being abandoned or lost and left to fend for itself. The offspring of the domestic (now considered feral) cat are usually never handled by people and become terrified. Many times, when approached by people, they will hiss out of fright. Given the chance, they will run away and hide. This is misunderstood as being vicious, but that is not true. Almost all feral cats that are trapped will cower to the back of the trap and shake from fright. Some even urinate due to uncontrolled fright. If the trap were to be opened they would not attack, but run away.
Ten to fifteen percent of the cats trapped are tame, abandoned cats. Some are even declawed. Others are elderly, guilty of nothing more than having lived with one person all their life until that person passed, and surviving family members decided to throw the animal out.