Definition
The legal umbrella term for any community where owners share ownership of, and responsibility for, common areas — including HOAs, COAs, and POAs.
Common interest development (CID) is the legal category that covers communities where private ownership is combined with shared ownership of common areas. HOAs, condominium associations, and planned developments are all types of CIDs.
The defining feature is the "common interest": every owner holds an individual property plus a shared stake in — and obligation to fund — the community's common elements. Many state statutes governing community associations are written around the CID concept.