According to Shia Islam death in this life is not equal to becoming nothingness until being recreated for the Judgement day, but there is another life style that we will experience after death and before the Judgement day. This after-death but before-the-Hour life is to happen in a world intermediate to this and after-the-Judgement worlds, and is called Barzakh or grave world (عالم البرزخ او القبر). Do not consider it as limited to the walls of grave, no its bigger than our present world but has many relations with the grave known to us as well, people may die in seas, never buried but burned, and etc. but still they will experience this grave world! Therefore, every human from the first time that is created before this life in the material world, as in the Dhar world (عالم الذر) or even before that(?), experiences a number of stages of lives:
- during living in the Dhar world life is the first that I am aware of its name, the Day of Covenant has happened during that life (the Covenant itself is kept in the Black Stone in Al-Haram Mosque, in Mecca), when none of us but Aadam were created in our material bodies. A witness for that from Quran is this:
When thy Lord drew forth from the Children of Adam - from their loins
- their descendants, and made them testify concerning themselves, (saying): "Am I not your Lord (who cherishes and sustains you)?"- They
said: "Yea! We do testify!" (This), lest ye should say on the Day of
Judgment: "Of this we were never mindful" [7:172]
and the world Dhar comes from Dharrah (ذره: a small whit) and Dhorriyeh (ذریه: descendent) comes from this as well! Also when Allah talks about a place of sojourn and a place of departure in the verse:
It is He Who hath produced you from a single person: so a place
of sojourn and a place of departure: We detail Our signs for people
who understand. [6:98]
The place for sojourn is the loins of fathers and the place for departure is the wombs of mothers. Also see [11:6] for a similar verse. That is, all of us have been existed since or before the creation of our first father's material body being created. Anyway, let skip this pre-present-world.
during living in the womb of our mothers. Note that death is sometimes compared to being born, there we had eyes and nose and hands and many other limbs we were not to use them and even were not caring about them, like they are unnecessary, but then we came to this world and saw how was the case if we had not even one single of those limbs, similarly we are told here to get prepare for our next life, some care their next life and some don't, and we will see who was righteous. Anyway, as death is an end to this-world-life being born is an end to the-womb-world-life.
during living in the present world, scientists are trying to understand it through their senses and intellectual power
during death, it seems to be almost instantaneously to our eyes but it is said in Ahadith that it may take either a short or a very long time, depending on the person who is experiencing it. Only note what Allah says after telling the story of the prophet Lut --peace be upon him--: [11:82,83]
When Our Decree issued, We turned (the cities) upside down, and rained
down on them brimstones hard as baked clay, spread, layer on layer
Marked as from thy Lord: Nor are they ever far from those who do
wrong!
Imam Sadiq --peace be upon him-- was asked about the last phrase in bold in the above cited verse and he answered this is about anyone who commit the same sin as did the people of Lut --peace be upon him--, which is the homosexually, not any of them will die unless with a similar chastisement. Then he was asked to clarify his answer further and he added they will be punished like the people of Lut --peace be upon him-- but you will not understand this. Also this is not only about those who commit such a sin but also those who are acquiescent about this sin being committed by the others, and this has also a witness in Quran.
- during living in the Barzakh world. This will again be short or long depending on the person, it is not somewhere to pray or make choice but rather something like Akherah (الأخرة: after the Judgment day), people will be rewarded or punished but not to the extent stated about Akherah, it may be considered as a weak form of Akherah, still to prepare people for that life. I'm not sure if Sunni people believe in such a world or not but it has some witnesses in Quran to exist:
"In order that I may work righteousness in the things I neglected." -
"By no means! It is but a word he says."- Before them is a Partition
[Barzakh] till the Day they are raised up. [23:100]
of which verse the name Barzakh is taken. Then:
In front of the Fire they are brought, morning and evening: And (the sentence will be) on the Day that Judgment will be established: "Cast ye the People of Pharaoh into the severest Penalty!" [40:46]
Which definitely is not talking about Akherah as elsewhere it is stated that chastisement at Akherah is continuous and not intermittent, by entering the fire and not being hold in its front and etc. There are actually many witnesses in Quran that states people after death are taken to an intermediate world before the Judgement day, e.g. see [56:83-94]. The Martyr being alive fed close to God are alive in the sense we are but in Barzakh, if I am not wrong. That some people dream, honestly, the death people he/she is seeing them in thei Barzakh bodies (souls and spirits have no shape, color, and etc. if you mention!):
We have decreed Death to be your common lot, and We are not to be
frustrated / from changing your Forms and creating you (again) in
(forms) that ye know not. [56:60,61]
That is to say, the reward and punishment in Barzah, altough being more sever than any reward and punishment in this world, again would be for/against that new body as well.
Also Shia People believe in a return-to-this-world (رجعة) for some specific people, those who are extremely good or extremely bad (but not having died due to a Allah's chastisement as He has said: But there is a ban on any population which We have destroyed: that they shall not return [21:95]). For example there is no martyr unless he/she would return to this life before the Judgement day, since they have not yet experienced the death and Allah has stated that everyone would taste it! [3:169 & 21:35] There are also many other witnesses for that among the historical ones being for example the miracle of Jesus --peace be upon him-- and the verse [2:259] in Quran.
during the Judgement day, which of course is so longer than to be called a simple day, it's so long to be precise, but maybe like a day compared to the eternal life after that and … , or the day here may refer to a period of time instead of 24 hours!
during Akherah after the Judgement day …
Now returning back to the world of grave (Barzakh), with the above classification I hope you can find quite many Ahadith and explanations based on them; only add the word Barzakh to your search keywords. A thorough explanation will take so long to be stated here. It starts from death in this life (not from being buried in a grave), contains the questions and answers of the angels in graves (two groups of people would not have these difficult Q/A), through which people would either immediately enter a Jannah which is said to be close to Najaf in Iraq at the Vadi-os-Salamm graveyard, enter a hell which is stated to be somewhere in Yemen at a desert named Barahoot (this is not fake although strange, our understanding of time and space is just too preliminary, note that there is also a relation between the world of grave and the very grave that we think to be familiar with, Barzakh is actually a hidden inside "باطن" to this world), the death people are freed every Friday's night (the night followed by Friday), so that it is stated that many of them would come to their families in this world looking for something good that we will do for them: Kheiraat "خیرات", and Barzakh will be until "one blast is sounded on the Trumpet" by which everyone would die for the second time for the world to be prepared for the Judgement day.
Hope this will help.
Godspeed.