http://scienceblogs.com/insolence/2008/ ... on_woo.php
Some excerpts (quoted in the article, the material in parentheses () are comments by the author):
The term indigo generation is somewhat of a blanket term that refers to the increased amount of the color indigo present in new babies Auras. Around 30 years ago some babies were exhibiting this phenomena and the number has steadily increased until now where every new baby is an Indigo. Although all indigo babies have this increased amount of indigo in their auras they can vary widely in other ways. The majority of Indigo's are simply reincarnations of the same group of beings who have always made up the human race. For instance you may be 35 years old and you are not classified as being an Indigo and you may give birth to a child who is an Indigo. The being incarnating as this child could be someone who you had been with in another life who was at that time not an indigo but just a normal incarnation just like you are now. If you were to die tomorrow and reincarnate next week you would then be an Indigo. It is not that the Indigo's are different beings but simply that they are incarnating some energies which were not being incarnated in normal people 30 years ago or more.
This being said it is also true that some indigo children are incarnating more than an increased amount of Indigo energy or light and that they may actually be incarnating parts of other beings along with themselves. Another possibility is that they are in fact a being who has not incarnated on earth before and who may have had incarnations on other planets. Another possibility is that a being who is a part of the human race, who has had many incarnations on earth may have had a recent incarnation on another planet and may now incarnate on Earth again with a very strong connection to this other planet or group of beings. In this way energies and consciousness from other areas and beings throughout the universe are being grounded on earth now.
The Indigo Children have been incarnating on the Earth for the last 100 years. The early Indigos were pioneers and wayshowers. After World War II, a significant number were born, and these are the Indigo adults of today. However, in the 1970s a major wave of Indigos was born, and so we have a whole generation of Indigos who are now in their late twenties and early thirties who are about to take their place as leaders in the world. Indigos continued to born up to about 2000, with increasing abilities and degrees of technological and creative sophistication.
The Crystal Children began to appear on the planet from about 2000, although some date them slightly earlier. These are extremely powerful children, whose main purpose is to take us to the next level in our evolution, and reveal to us our inner power and divinity. They function as a group consciousness rather than as individuals, and they live by the" Law of One" or Unity Consciousness. They are a powerful force for love and peace on the planet.
The Indigo and Crystal Adults are composed of two groups. Firstly, there are those who were born as Indigos and are now making the transition to Crystal. This means they undergo a spiritual and physical transformation that awakens their "Christ" or "Crystal" consciousness and links them with the Crystal children as part of the evolutionary wave of change. The second group is those who were born without these qualities, but have aquired or are in the process of aquiring them through their own hard work and the diligent following of a spiritual path. Yes, this means that all of us have the potential to be part of the emerging group of "human angels".
Normal Indigo's: A normal Indigo is a recent incarnation of a normal person who has been incarnating on Earth for some time. The only difference between this incarnation and the ones of the past 10,000 years is that this time they are incarnating more of their Indigo energy. These people are typically full of samskara's just like everyone else and have a lot of work to do on clearing their astral body. (Hmmm. I probably do have a lot of work to do to clear my astral body.)
Dual Indigo's: There is another type of Indigo who has along with their own light body agreed to incarnate some forces of consciousness from another being. This is always done in agreement and the two beings usually have a relationship already. The main incarnating being will be a member of the human race just like the normal Indigo's who have many samskara's and who has lived many lives on earth. They have likely done spiritual work in past lives which has brought them to a level where they can safely help another being to incarnate with them. Indeed they may have been preparing for this incarnation for quite some time and will have become close to the other being. (Wow! Too beings in one brain! Wasn't there a Star Trek episode about that? Come to think of it there were more than one. I had no idea that these episodes were apparently documentaries.)
Extra Terrestrial's: Another possibility is that a being who has been incarnating on other planets and in other dimensions may incarnate on Earth. They are not a part of the human reincarnational cycle and although they may have incarnated here at some point in the past they can still be seen as Extra Terrestrials. Their make up is different to ours and they will not have the same type of samskara's as normal humans. There are a huge number of Extra Terrestrial races in our universe and they differ very widely. For this reason it is hard to describe what an extra terrestrial might be like. They could be extremely intelligent such as mathematical geniuses, they could be musical geniuses or extremely psychic. They will nearly always have an extreme talent which sets them apart from normal people and their heart may seem to be incorruptible. Just their energy alone will be different enough that people will notice that they are somehow different. If you meet one of these beings you get a feeling that they are different even if they look totally normal. If you are one of these beings you probably already know because they have such a strong connection with their home planet and the race of beings they belong to. They usually remember where they come from at a very early age and know that they are different. As they don't have the same sort of samskaras as normal humans their consciousness remains very clear even after going through childhood. (So that explains it. I'm E.T.!)
Recent Off Planet Incarnates: Another group of Indigo's are those who are a part of the human race but who have had recent incarnations on other planets. Like the Extra Terrestrials these beings have a strong connection to the planet that they were on, they help to ground these new forces and hold a channel for these other races to see what is happening here. This has been used as a method instead of ET's actually coming here because this can be very hard for them. It is much easier for a human to go to other planets because the energy there is so clear. Many of them have little or no negativity at all so it is extremely hard for ET's to incarnate here because they lack the defenses against our extreme negativity. Only the most adventurous of Extra Terrestrials have volunteered to come here. (I'm guessing my attitude towards the whole Indigo concept is part of that "extreme negativity" that these incarnates don't like.)