Generation gap is difference in attitude and behaviour between people of different generations.
For example, old generation would accuse the new of being disobedient and lacking in values. While the new generation would accuse the old for being too rigid and outdated.
A son was bound to chose the profession of his father and live the same life which his father has lived. The external environment too did not change much. Society was the same wether it was the 14th century or the 15th century. Same economy, same lifestyle.
Father, being the experienced person would understand the needs and dilemmas of his son, as he has faced the same in his own life. There was no generation gap then.
It all started post industrial revolution. When the society started changing. But the significance was realized only in the 20th century, when mass media led to massive changes in the social environment. Dress, food, music and dance all would change every 20 years. Even ideologies would change.
Father and son were separated by different lifestyles. Son would face different choices and dilemmas, his father would have no answers to. Son would look elsewhere for answers, but his father would want him to listen. Result is a conflict.
That’s generation gap.
Today the pace of change has only increased. So the generation gap is expected to be increasing too. This pose a challenge to the new parents. They are expected to be adaptable, understanding and tolerant to avoid inter generational conflicts.