Babies in the first year explore their surroundings through their senses such as seeing, touching, smelling, hearing and tasting. When a baby wants to investigate further a toy or whatever it grabs, this often means putting it in his mouth.
If we want to identify an object without looking at it, we will pick up the object and move it around in our hands, touching with our fingers until we figured out what it is. The reason we use our hands is because we have more sensory nerves and brain space devoted to our fingers, than anywhere else in our body.
In babies it is not the same. The most highly developed sensory area in babies is in their mouth. So when a baby puts an object in his mouth, he is exploring it with the sensory nerves. Is it hard? Is it soft? Is it tasty? Does it make a sound? The answers of these questions babies found through exploring the object with the sensory nerves in their tongue and lips. Mouthing helps babies learn all about different shapes and textures.
Babies often mouth objects more when a new tooth is just breaking through the gym. In this case try giving your baby a teething toy that has been chilled in the fridge for some relief.
In this stage of child development mothers are often worried about the risk of choking. To reduce the risk of choking, babies should be allowed to play only with toys that are too big to fit in their mouth. Another thing that must be considered is the smoothness of the object. The toys should be smooth enough not to scratch the baby.
Another worry for moms is the germs. If baby is playing with a toy that was on the floor, there is little chance it will make him sick. Frequently washing hands and toys will be enough to protect the baby. Also sharing toys with sick kids is not a good idea. This way viruses and bacteria can pass and make kids sick.