Youth is the time of life when someone is young : the time when a young person has not yet become an adult.

a : the time of life when one is young; especially : the period between childhood and maturity.

Youth can refer to the entire time of life when one is young, including childhood, but often refers specifically to the time of life that is neither childhood nor adulthood but rather somewhere in between.

Youth also identifies a particular mindset of attitude, as in “He is very youthful”. The term also refers to individuals between the ages of 16 and 24.

: the time when something is new and not yet established – being the appetite for adventure over the life of ease.” (girls- desiring to fall in love, and boys- desiring to experience a life which goes beyond the limited perimeters of their own family).

A young male between adolescence and maturity.

During the time of one’s youth (age of 19 to 25) that is a time when the boys become militant (willing to argue and defend their own opinions). 

And this is the reason why boys go for military training during the stage of youth.

Most of the revolutions (changing of mindset on how one perceives life) occurs during the period of youth.

It is the time of a person’s life in which they make choices which will affect their future.

Read also about the article called adolescence.