Overall-16Sanskar

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The Smritis and Grihasutras explain the sanskaras. Different Grihasutras differ on both the names and numbers of sanskaras. While the sage Aswalayana lays down 11 customs, Bauddhayana, Paraskar, and Varaha explain 13. Sage Vaikhana has 18 and Maharishi Gautam talks of 40 sanskaras and 8 self-qualities. However, the 16 sanskaras that Rishi Veda Vyas propounded are considered the most important in a Hindu's life.  
Sanskar [also spelled as Samskar] give a spiritual touch to the important events at different stages of a life – right from pre-birth to post-death. As part of celebration of each sanskar, God is invoked and worshipped by chanting of Vedic Mantras. 
Sanskars means Sanshodhan-Parishodhan-Parishuddhi. Through Sanskar, Shudhi (purification) of Jeev (soul) is performed through all three types (Adhyatmik-Aadhibhautik- Aadhideivik).
These sanskars are: 
Garbhadhan (Conception) is performed with an objective of the development and continuance of the progeny of the parents and with a view to get a noble and intelligent child. 
Punsavana (Fetus Protection) For the physical and mental development of the baby in the womb of the mother
Simantonayana (Satisfying Wishes Of The Pregnant Mother) performed at different stages of pregnancy, objective to keep the mother free of any worry. The fetus emulates the achar-vichar-shravan.
Jatakarma (Birth Rituals) It is performed on the six days from the birth, for the purification of the house. Honey and Ghee is also touched on the lips of the child. It is also called Shashthi [6th] pooja.
Nam)karan (Name–Giving It is performed on 10th, 11th or 12th day. The child gets name from the Hora Shatra, based on 27 Nakshatra and the position of the moon at the time of child’s birth. 
Nishkramana (Taking The Child Outdoors) The child is taken out of the home for the first time and sees the Panchmahabhut. It is done at the time of Namkaran or on 4oth day or other day, as per local custom.  
Annaprashana (Giving The Child Solid Food) On sixth month, the child is given solid food (anna) for the first time, with poojan of Annapurna Devi.
Chudakarana Or Mundan (Hair Cutting), Between the age of one-three- five years from the birth, hair of the child is removed.
Karnvedh (Ear Piercing) Ears of a child pierced in the third or fifth year, with the commencement of Surya Puja; the father says “Oh God may we hear bliss with our ears” in  the right ear of the child. 
Upanayana Or Yagyopaveet (Sacred Thread)

It is the ceremony of wearing the sacred thread called Yajnopaveetam [Janeu]. It is generally performed between the age of 5 and 12. This Sanskar is second birth for child – A spiritual birth. The ceremony has six parts: –
Puja: worshipping the Gods,

  • Havan: sacrifice,
  • Shiksha: teaching the morality and duties in life,
  • Bhiksha: begging as a renounced Brahmchari of Gurukula. 
  • Diksha: giving the most sacred Gayatri Mantra to the child, and
  • Blessings: child is bless by all Gods, Goddesses, ancestors, and elders
Vedarambh (Study Of Vedas And Scriptures)  It is done along with Upanayana, starts in the learning of Vedas and Upanishads in ‘Gurukula’ or ‘Pathashala’. In the beginning of each academic period there is a ceremony called Upakarm and at the end of each academic period there is another ceremony called Upasarjana. 
Samavartana (Completing Education) It marks the end Brahmacharya Ashram and end of formal education. 
Vivaha (The Marriage), Vaanprastha)

It denotes the entry into the Grihast Ashram. Vedic marriage is viewed as sacramental, and is a lifelong commitment of one wife and one husband.

(PAY BACK PITRI-MATRI RIN)

Vaanprastha

 This ceremony marks completion of Grahastha Dharma.

(PAY BACK RISHI RIN)

Sanyasa

A  sanyasi is supposed to renounce the world and lead a life of study and meditation by living on alms.

Antyeshti (Last Rite). 

Antyeshti (Antim-Sanskar - Last Rites). When death is imminent, a small piece of gold, tulsi leaf and drops of Ganga water are put in the mouth of the person on the death bed. The body is laid on the ground with the head towards the north. The eldest son generally performs the last rites. The dead body is washed, perfumed and wrapped in a new white cloth and decked with flowers.For ten days following death, food is not prepared at home and relatives and friends take the responsibility of getting food for the family.

The Chinmaya Mission's Upanishad Ganga- Episode 19 to 21 shows this very well. Links to three episodes are povided below.
You may also download pdf from: 8232.pdf (ignca.gov.in)
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