The ancient Greek philosophers were concerned about this and took very seriously the notion of the community or "polis" which is the origin of our word "politics." Apart from the polis the citizen was lost. The community created a shared sense of belonging and this seems to be an important trait in any good community.
Another very important aspect seems to be shared interests; not in the sense of liking similar things but in the sense of having an interest in the welfare of the community. The community and its welfare matter to the individuals in it. They each have a stake in the success of the community. They not only benefit from the community but contribute to it as well.
Of course, in the perfectly everyday sense of the word, shared interests are also important. We find ourselves mostly in communities of choice either through work relationships, friendships, volunteering, and by participating in online communities.
Many have begun to wonder whether the loss of a real connection in online communities makes them less than good communities. Have we lost the ability to form communities in the real world? Personally, I don't think so but it is a question worth asking. The internet seems to have the potential to widen our communities and grow them in new and positive ways. Sure, there are problems and we can't forget the limitations but there are also advantages. Issues which might normally impede the formation of communities such as race, socio-economic status, and culture can be more easily overcome in online communities.
In the book Wikinomics, Don Tapscott uses ebay as an example of just such a community. He writes about a young adult with handicaps who is making so much money on ebay that his parents have quit their jobs to support his ebay store! Of course the money is nice but the point of the story is that on ebay he is not handicapped. He is a member of the community equal in every way to every other member. Such things do not matter online. The same would hold true for many of the barriers we sometimes encounter in our formation of communities in the real world.
But, some of these barriers are worth overcoming and facing the challenge of doing so may be a good thing as well. The philosopher John Rawls addresses the notion of a good community by pointing out that any just society will be one with inequality but only if the inequality benefits the least well off. Clearly, concern for our fellows in our communities is an important aspect of a good community.
In conclusion perhaps we could summarize some important traits of a good community as follows. Participation should be voluntary and beneficial to the individuals involved. The individuals should have similar interests in the sense both of having a stake in the success of the community and in the everyday sense of the term. Individuals within the community should be concerned for the welfare of the other individuals in the community with a particular eye towards the least well off.
