Death is just a hairbreadth away from Life.
What does happen just before death, at the time of Death and after death?
For the first two points and signs of Death, according to Hinduism, please read my articles Signs of Death,Hinduism.
What does Hinduism say on Life just afer death?
Soul has five layers.
Annamaya Kosa, the subtle body made of the essence of Food,
Pranamaya Kosa, of Life’s breath,
Manomaya Kosa, made of mind’s impressions,
Vignanamaya Kosa, the subtle reposited impressions of Knowledge and
Gnanamaya Kosa, the level of wisdom, discerned knowledge.
The last one Anandamaya Kosa is an immediate Attribute of BrahmanThe Reality.
When all the other Kosas( sheaths) , except Gnanamaya Kosa are dissipitated, the Gnanamaya Kosa gets merged, in case of Realized Souls, with Brahman or the knowledge that it is different from Brahman disappears.
The Death ceremonies conducted for the first twelve Days in Hinduism, more specifically in the case of Brahmins,relate to these aspects.
Once the life leaves the body it becomes Sava,without Auspiciosness,Shiva.
The human body has two aspects,Sthula,Gross and Sookshma,Subtle.
The physical frame is the gross aspect of Atman.
Sookshma Sareera,Subtle body is a conglomeration of the essence(Rasa) of Food(Anna),Prana(life energy),Mind(Manas),Knowledge(Vigyana) and Consciousness(Ananda).
All these subtle aspects draw their nourishment from the Five Gross elements,Earth,Water,Fire,Air and Ether(Prithvi,Appu,Agni,Vayu and Akasha).
Each of these subtle essences nourish the body and facilitates the enjoyment,both pleasant and unpleasant,depending on one’s actions,Karma,by the Unrealized.
Once Life ebbs away,the physical frame called Sava is cremated and the subtle body is called Pretha.
The functions of the Sava ceases but the subtle body,Pretha remains,though it remains invisible.
On the day of death,after the ceremonies are conducted at home ,officially christening the body as Pretha,washing it,removing everything worn,adorning with Vibhuthi or appropriate castemark,declaring the son and if the deceased had no son,the one who shall conduct the Andhima Karma,Final Rites is designated as such, along with symbolic fire which was lit as soon as the person died,the body is moved to the Crematorium,with the Grandson/s showing the light with a torch.
At the crematorium,the body,before consigning to flames,is addressed as Pretha by the son,thanking the person for bringing up the children,declaring that the son would perform all Karmas to enable the Sookshma sareea to join the ancestors.
At the crematorium the body which has sprung from the five elements,Earth,Water,Fire,Air and Ether is retuned.
The body is laid on the ground and rites are performed and mantras chanted returning the body to Earth.
Water is filled ( half pot),son walks around the body in an anticlockwise direction three times,a hole is made in the pot at each perambulation(total three) and water is allowed to flow to the earth signifying the return to Water.
Fire is lit from the brazier to the body returning it to Fire in the condition the body came into being,that is bereft of anything.
Air,Vayu is worshipped along with Aakasa,Ether praying they take their composition in the body.
Food, in the form of Rice is offered to the body by relatives as the last food offered to the body stating that further food will be for the subtle body.
If the Thithi when cremating is different from the Thithi when death occurred,the ashes/bones are collected by the son wearing Kandankathri Vegetable,( which incidentally is an antibiotic to prevent infections from the bones that mat may be found in the ashes),on the day of death and is consigned to ocean.
There is no Theetu for the first two nazhikai from the time of death(40 minutes)
The Kartha must take bath after entering house,( he must enter the house after washing his feet outside the the house,so must the others)
He should change to fresh Dhoti,not new and take light refreshments,no meals.
The light which was lit at the time of death near the body must be kept burning till 12th Day ceremony is complete.
Food is not to be prepared at home and it can be received from relatives.
Sandhyavandana is not to be performed for the first two days,the day of death and collection/immersion of ashes.
It has to be performed from day three.
If collection of Ashes is done on the same day of death,Sandhyavandana may be performed from the next day.
No other Vaidika Karma must be performed till the 13th day function is over.
The karmas to be performed from The Third day follows with meaning behind them