Key Difference: Infants and toddlers are young babies. Infant is generally used for babies who are 0 to 12 months old. However, toddler is used for babies who are 1 to 3 years old. Both are marked by different physiological characteristics.

Infants are babies belonging to the 0 to 1 year of age-group. This is a very important year of a child. During this year, babies learn many things like focusing their vision, reaching out, exploring the things around them, and many more. During the infancy period babies tend to develop a special bond with their parents and caregivers. Breastfeeding is often recommended to mothers for the babies for about the first 6 months.

During the completion of this period, an infant is able to walk with one hand held. An infant is also able to recognize objects by name and understands few simple verbal commands. Infant is referred to as a toddler after the completion of 1^st year.

Toddler as the word signifies, it represents a young child who toddles. It is used for a child between the ages of one and three. During these years, lots of changes occur in the child. For example- usually at the first year of age the weight of the baby gets tripled.  A toddler also grows to a height of approximately 50 percent over length during birth. A toddler also starts responding to sounds and starts uttering few words like ma, mumma or papa.

During this time, a toddler is also able to get some understanding of connection of names with objects. During the second year, typically a toddler weighs about 11 to 13 kg and height varies about 80-82 cm. On reaching the 2^nd year, a child is able to walk sideways and backwards. A toddler is also able to walk alone with wide based gait. During the second year, a toddler is able to walk up and down stairs on both feet. He is also able to manage the control of spoon properly.

Comparison between Infant and Toddler:

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