Vanaprastha is one of the four ashrams / stages of life as per Hindu Shastra.
(3)Vanaprastha refers to the third of four Ashram.
The stage lasts for twenty-four years from around the age of forty-eight to the age of seventy-two. It is a time for gradual withdrawal from worldly concerns and share wisdome from experience.
The other three ashrams of life are

(1) brahmacharya (student),
(2) grihastha (householder),  and
(4) sannyas (full renunciation).

(3a) During the stage of vanaprastha, one may share the wisdom that one has accumulated in the earlier stages of life. That is, one serves as a mature counselor. Although the vanaprasthi mostly withdraws from his involvements in the world.
(3b) In the past, vanaprastha referred to a period in which a person prepared for the ultimate renunciation of sannyas by retiring to the forest or a solitary place for meditation.The stage of vanaprastha, in particular, is ignored in the modern world. Nowadays, the information and technology people the purpose of sharing one’s life work has lost some of its meaning.
The system of four ashrams was founded in India during a higher spiritual age, during which the purpose of life was widely understood.Nowadays, the ideal system of life is not widely observed in modern India. Under the direction of a guru, special schools and communities may uphold the system.