In Hinduism, the 16 Sanskars are a set of religious ceremonies performed during the life of a human being to purify the soul and uplift it towards Moksha-Mukti. The Sanskars are performed for the physical, social, and spiritual development of the individual. The 16 Sanskars are divided into five categories:

1. Pre-natal Sanskars: These Sanskars are performed before the birth of a child and include Garbhadhan, Punsavan, and Simantonnayana.

2. Childhood Sanskars: These Sanskars are performed during childhood and include Jatakarma, Namakaran, and Nishkramana.

3. Educational Sanskars: These Sanskars are performed during the education phase and include Karnavedha, Upanayana, and Vedarambha.

4. Marriage Sanskars: These Sanskars are performed during marriage and include Vivaha and Vanaprastha.

5. Death Sanskars: These Sanskars are performed after death and include Antyeshti and Shraddha.

Each Sanskar has its own significance and is performed with the chanting of Vedic Mantras according to each ritual. The 16 Sanskars are considered an essential rule for human beings, and it is mandatory to observe them. A person who does not observe these Sanskars in their life is considered incomplete, and if one or two Sanskars are left out, there remains a defect in their life. The 16 Sanskars are an important part of Hinduism and are believed to impact human life scientifically.