Community in Fiction

On Traipah, people generally live in extended family groups instead of the standard Western nuclear family thing. Since Ah'Koi Bahnis can live to be as much as 200 years old, this means BIG families. And cities being mostly for commerce, with not many people living in the cities, most live in villages, so the village communities become very close. At least, that's the pattern on one continent.
It seems like the Duenicallo, one of the sentient carnivore species on Traipah, is a little different. There are a variety of different patterns on their home continent, Ah'Bahss, depending on where they live. Ah'Bahss has vast plainslands, and also has forests, mountains, and other ecosystems. On the plains, there are tribes. Even some of the Ah'Koi Bahnis live on the Ah'Bahss plains in tribes, riding animals filling a similar role to horses (which Duenicallo do not need and couldn't ride if they wanted to).
Meanwhile, the other carnivorous sentient species, the Shao'Kennah, live in small groups in the jungles and nest in the trees. They have tribes, but they're spaced out more, Shao'kennah being more territorial than AKB or Duenicallo.

In my Mindeodean universe, the Joquari live their whole lives on a single spaceship, since they are adapted to zero-g and would die on a planet. These ships often travel together in convoys, wandering through space like some kind of space Roma, trading at the different stops.

In "Carbon and Silicon," Fiomi's people, the Zedaleph, are replicated in yearly batches in factories around the world (they are a machine race, replication is their reproduction), and how many are thus replicated depends on a number of factors, like how many Zedaleph have died or moved to other planets, or moved *from* other planets. They are named by the order they were made and their batch number. (I think Fiomi's name meant something like "30 of 50".) These yearly batches are raised together, in something resembling a cross among an orphanage, a school, and a family, with yearly batches from previous years and later years. Though they try to keep these family batches small, often requiring many of these Learning Centers around the world. Once they've been assigned their family, that doesn't change. But for all the mechanistic way they reproduce and decide who raises the kids, Zedaleph are pretty human-like in personality despite the fact they were not made by humans and meet one for the first time ever in "Carbon and Silicon."
In fact, the whole notion of sentient organics is new to them and extremely controversial. It had previously been dogma that organics were too stupid and primitive a lifeform to develop sentience, a dogma based on the fact they'd never before seen organics as anything other than a pest, as literal vermin disrupting important systems. Other silicon races had eliminated organic life altogether on their planets. The Zedaleph put up with the organic lifeforms on their world because they thought the sky was much prettier when it was blue, and were fond of the ocean. (They also use the ocean for power.)

Oh, and of course, there's dark sorceress Lyria Spellspinner and her family. Having been exiled from her tribe, she moved to Vraygrotta after wandering around a lot learning different magics, including the forbidden art of soul magic (the art of changing the soul of a person or object) and DNA manipulation. She has 4 very close "children" who are her creations, only one of which actually looks related to her (the only one to look human). Her servants are all "flesh golems," meaning they were reanimated corpses whose appearance was altered and given new minds. (But more than that, flesh golems may be magically reanimated, but they don't depend on magic to keep living. They were dead, but are human once again.) Lyria is very protective of her family. She can be sweet and kind and do great feats of good, but threaten or hurt her family, and she can be truly terrifying, killing the threat without remorse if the threat is lucky. I'm having loads of fun with these characters!

The other men on a boy's first raid become his kin. The other women who are menstruating when a girl gets her first period become her kin... Neat! *very intrigued*

In Addergoole, my web-serial, students are grouped by Cohort (year in school), cy'ree (Students of the same Mentor), and crew (a group of like-minded individuals, often sharing a suite of rooms), as well as coupling off in short- or (rarely) long-term relationships. I thought, at one time, of designing school scarves (nevermind that the school is climate-controlled & underground) but the complexity would be a bit maddening.