The oxidation state of an atom is the fictitious charge that an atom would have if all bonds between atoms of different elements were 100% ionic. Thus, oxidation is better defined as an increase in oxidation state, and reduction as a decrease in oxidation state.
Most babies take their first steps sometime between 9 and 12 months and are walking well by the time they're 14 or 15 months old. Don't worry if your child takes a little longer, though. Some perfectly normal children don't walk until they're 16 or 17 months old.
Many babies walk by their first birthday, but there is a wide range of what's considered normal: anywhere from 9 to 16 months. Temperament seems to play a role in when a child takes on major developmental milestones. A baby with an easygoing disposition may approach walking more cautiously.