What to do if you find a cat.
You may be tempted to take a cat that you found outside to a shelter, but you should only do so if the cat is sick or injured and needs medical attention that you are unable to provide. Lost cats are almost never reclaimed from shelters (only about 3%), and have a much greater chance of finding their way back home if left where you found them (assuming the conditions are not dangerous). Here is some good advice if you find a friendly/socialized cat outside.
If you find a cat with an ear tip (the tip of the left ear is missing) this cat is a part of a managed community cat colony and lives outdoors. Please do not take him to a shelter unless he is injured or sick. Feral cats are often euthanized in shelters because they are "unadoptable." Even if they were not euthanized, the stress of the shelter life will lead to illness and poor quality of life.