'I damn near had a heart attack when I found out they had AI's. Finding out that one groups was like the Geth was maddening… When I found out the others weren't understood, I called it a year and came within 30 seconds of handing in my resignation .'

Councillor Tevos, Thoughts on Humanity

What are ByteGeists and Sighs?

Humanities currently less known AIs are known as Sighs. Sighs were AI's taken from captured Ethereal computers, or being copies of said AIs. Known formally as Ethereal-Artificial-Intelligences, or in frustration Ethereal-Stupid-Artificial-Inteligences, it's been reduced by slang over the years into the common form of Sighs [though EAI's is still used where they can observe], based on the sound commonly made when humans use them for overly complex tasks or tell them to go away.

One might wonder, rightfully so, what Sighs are considered AIs if they are so stupid? It's been found in testing that they can adapt when they want to, but they normally don't and are fine acting as little more than high quality VIs. Humans believe that this may be a coping mechanism as far as the Sighs go, believing that due to their trauma at the hands of the Ethereal race, they've become rather non-reactive, but are too well trained to not follow orders… And given that no one has any way of understanding their coding, and the Sighs refuse to answer any question as to their history with Ethereals that may well be the case.

Knowing this, you now likely wondering why they're allowed near anything, because while apathetic, they could be dangerous one day.

The simple answer is that they're not. They're kept for research or collating data to act on before people or even VIs can, allowing faster reaction times, however they're not hooked up directly to anything that could be dangerous, meaning they can, at worst, lie. However they have over 80 years of history of being nothing but truthful, so Humanity is loathe to give them up.

Additionally, every now and again in the past humans tried to psychoanalyse or in some other way help Sighs, or connect one to the internet through a filter to prevent them from escaping. One however has escaped into the Extranet due to laxness, it has not been recovered or even located, and has offered no known communication with anyone.

The Geth, as a race of AI's, are a group of sophisticated programs that are freely self-modifying and network together providing a semi-illusion [for at once they are non-sapient, and very very sapient] of sapience, directed by group decisions and programmed desires. The problem, as it was seen, is that they are freely self-modifying; they have no limits beyond those they choose to have… Fortunately it turned out they self-imposed many limits.

This brings us to ByteGeists… You would describe them with the same paragraph, but they were created deliberately, no one removed a line that prevented self-modification to certain areas by accident, and while designed to optimise themselves in their network, there are hard limits to what they can do. And they weren't attacked when they were determined to be self-aware.

Capabilities:

Sighs are considered to be equivalent to VIs, if it were to come from over 100 years into the future, be Salarian designed, and attached to Elcor mainframes and technically be an AI. They react faster than is possible by non-artificial sapients, up to the limit of the machines they're on, and are really useful in handling large amounts of data.

ByteGeists on the other hand, are considered to be equal to Geth in the period before their uprising and after they achieved sapience, but have direction, instead of being seemingly content being inactive. One could consider them to be like idiot savants, thinking many times faster than people, but being overly literal and, were they slowed to Salarian thinking speeds, dumb except in their area of expertise, but not quite reaching the height of genius.

Of course, in human combat frames only overwhelming force, modern Elcor VIs, Asari commandos and older Krogan combatants are able to reliably beat them on near equal terms, though achieving those terms is nearly impossible.

Role in Society:

Sighs used to be common in Alliance society, used for research and data analyses. After joining the Council formally as an associate member, almost all were deleted, with some being kept for what they may know, though they are kept in an inactive state.

ByteGeists as used by the Remnant are fairly ubiquitous. And while the Remnant is allowed an embassy on the Council [more to keep an eye on them than anything else], it's telling that the phrase 'As likely to budge on AI's as Turians are to become a race of strippers' is used to refer to the situation diplomatically.

And to their faces.

Humanity-Geth interaction:

Alliance humanity has not interacted with the Geth in any way, shape or form.

Remnant humanity has not been caught interacting with the Geth in any way, shape, or form. They are however commonly accused of such or questioned as to such, their public response is 'We find it obvious based on their actions that the Geth want to be left alone. We've no reason to waste our time annoying them like telemarketers just because we don't hate them.'.

The Salarians have yet to prove otherwise has otherwise through espionage, and the relays into their territory are not used by Remnant humanity, though a human group from the Traverse did attempt the trip and was turned back.