The timeline functionality shows when there are three or more statements that have been dated. The most obvious dates are the life events; birth, death, marriage and children. For many people other dates are as significant; Mr. Gandhi for instance was born in India, studied in London, returned to India, took a job in SouthAfrica and returned to India.
For authors the dates of publications of books are relevant. For military men the battles they fought, for politicians the positions they held, for people competing in sports the competitions they participated in. There are the people who won prizes or received awards in any field.
There are so many things that are dated and when they are presented together on a timeline in a context, they provide a different kind of understanding.