English cannot express the ‘Dreaming’
‘Dreamtime’ or ‘Dreaming’ has never been a direct translation of an Aboriginal word. The English language does not know an equivalent to express the complex Aboriginal spiritual concepts to white people.
Aboriginal languages contain a lot of words for spirituality and beliefs, such as
- tjurkurrpa, jukurrpa, tjurgurba (Pitjantjatjara people, north-western South Australia),
- altjeringa, alcheringa, alchera, aldjerinya (Arrernte people, central Australia),
- ungud (Ngarinyin people, north-Western Australia),
- wongar (north eastern Arnhem Land),
- bugari (Broome, north-Western Australia).
There is no spelling orthodoxy because native speakers did not write down Aboriginal languages.
'The Dreaming' or 'the Dreamtime' indicates a psychic state in which or during which contact is made with the ancestral spirits, or the Law, or that special period of the beginning.—Mudrooroo, Aboriginal writer 
Should I use ‘Dreaming’ or ‘Dreamtime’?
Aboriginal spirituality does not consider the ‘Dreamtime’ as a time past, in fact not as a time at all. Time refers to past, present and future but the ‘Dreamtime’ is none of these. The ‘Dreamtime’ “is there with them, it is not a long way away. The Dreamtime is the environment that the Aboriginal lived in, and it still exists today, all around us,” says Aboriginal author Mudrooroo . It is important to note that the Dreaming always also comprises the significance of place .
Hence, if we try to use an English word, we should avoid the term ‘Dreamtime’ and use the word ‘Dreaming’ instead. It expresses better the timeless concept of moving from ‘dream’ to reality which in itself is an act of creation and the basis of many Aboriginal creation myths. None of the hundreds of Aboriginal languages contain a word for time .
We are the oldest and the strongest people, we're here all of the time, we're constant through the Dreaming which is happening now, there's no such thing as the Dreamtime.—Karl Telfer, senior culture-bearer for Kaurna people, Adelaide 
Note that the Dreaming is not the product of human dreams. The use of the English word ‘dreaming’ is more of a matter of analogy than translation.  Take care to use appropriate terms for Aboriginal topics to avoid offence.
The creation process
The Dreaming also explains the creation process. Ancestor beings rose and roamed the initially barren land, fought and loved, and created the land’s features as we see them today. After creating the ‘sacred world’ the spiritual beings “turned into rocks or trees or a part of the landscape. These became sacred places, to be seen only by initiated men.” 
The spirits of the ancestor beings are passed on to their descendants, e.g. shark, kangaroo, honey ant, snake and so on and hundreds of others which have become totems within the diverse Indigenous groups across the continent .
Spirits don’t belong to anyone and can be accessed by everyone. “No-one owns a spirits,” says Quandamooka woman Evelyn Parkin. “You can have what I have got if you’re in touch with the spirit.” .
It is interesting to note that many Aboriginal people also use the term ‘Dreaming’ to refer to their concepts about spirituality. This might be because some of them find ceremonies or songs in a state of dreaming, a state between sleeping and waking . Strictly speaking, dreaming and mythology can be considered as the same thing: the deep mental archetypes and images of wisdom which we take on to be guided by them when the conscious mind is in a state of quietness .
The fact that the Dreaming is still around Aboriginal people is a fundamental difference to other spiritual beliefs. In Christianity, for example, the spiritual world is ‘heaven’, and many Christians believe it is reachable only after death and never while the person is still alive. (Those who find heaven inside might disagree, but such a discussion is beyond this article.)
Aboriginal man Midnight Davies describes how all-encompassing the Dreaming can be for Aboriginal people: 
“The Dreaming is, however, more than just an explanation of cultural norms, and where we came from. The Dreaming is a complete guide to life and living - it is an encyclopaedia of the world. It is not just stories - it is art, songs, dance; it is written into the land itself.
“Through the Dreaming we are taught knowledge of plants and animals, to us many of the flowering plants are treated as signs of animals available to hunt, fish about to appear, fruits about to ripen; the movement of the stars foretells the changing of weather, the birth of animals, the time for ceremony and gatherings.
“The Dreaming completely surrounds us, we are shown proof of it everyday. It’s not some old book written thousands of years ago, it is the living world itself. The Dreaming belongs to every Aboriginal person - it isn’t the sacred property of a few priests/rabbis/imams, it is the property of everyone - every ceremony, every right, every tradition, every bit of knowledge is destined to be known to an individual sometime within their lifetime.
“The Dreaming was not designed to be just practised one day a week, or to only be turned to only in times of need - it is designed to be lived in every moment, and to shield you from those times of need. It serves as a guide to day-to-day life, a guide to the spiritual side of life.”
What we draw on from our memories, and think, imagine and create in our daily lives is our dreaming.—Djon Mundine, Bundjalung man and Aboriginal Curator, Campbelltown Arts Centre 
Dreaming gives identity
Each Aboriginal person identifies with a specific Dreaming. It gives them identity, dictates how they express their spirituality (see below) and tells them which other Aboriginal people are related to them in a close family, because those share the same Dreaming . One person can have multiple Dreamings .
Each form shares the spirituality from the ‘Dreaming’. It is during ceremonies that the trance-like dreaming state seizes the Aboriginal people and they connect with the ancestral beings .
Watch three Aboriginal men explaining what the Dreaming (tjukurrpa) means for them and how Dreaming stories encode information:
Here is a sample story:
Watch more Dreaming stories: Sam Taylor has put together a few Dreaming videos.
Poem: Dreaming stories
My culture is my identity. Dreamtime stories tell the life of my people. Growing older. Hearing stories of my ancestors living off the land Becoming one with the creatures Even though I haven't met them I feel this unbreakable connection Through the stories I have heard. The stories that have been passed down through generations. These stories are living through us. Without our culture we have no identity And without our identity We have nothing.
Poem by students Kiarra and Karri Moseley and Luke Bidner . Read more Aboriginal poetry.