There are two types of baby birds: nestlings and fledglings.
...Nestling is a baby, without feathers or with pin feathers, that has not left the nest.
...Fledgling has feathers and is learning how to fly. It does not return to the nest once it leaves it.
If a nestling is found, it should be returned to its nest. It is ok to touch the baby because birds have a bad sense of smell and the parents will not smell your scent on the baby. If the nest cannot be reached, make one out of a hanging plant basket. Poke holes in the bottom, line it with pine straw or grass, and hang it in a bush or tree near the location that the baby was found. The parents will return when they hear the baby cry.
Fledglings are learning to fly, so they do not stay in the nest. If a fledgling is found, please leave it alone. If it is on the ground, put it in a bush so that it is less vulnerable. The parents are not always with the baby because they are looking for food to feed it. Again, touching it will not harm it or cause the parents to reject it.
Baby birds should be taken in only if one of the following occurs: both parents are positively dead, the baby is injured, or the baby is in real danger. When taken in, the baby should be placed in a dark box and brought to the Environmental Studies Center. It is against the law to keep any wild bird without a permit and it is also best for the bird if it is cared for by a knowledgeable person. Raising a baby bird takes a lot of time. In fact a nestling has to be fed every 20 minutes from dusk to dawn. The best thing to feed a baby, until it can be brought to a wildlife rehabilitator, is dry dog or cat food that has been soaked in water. Never give it liquid with an eye dropper!