Content types and site columns are the foundational elements of SharePoint, but they often get misused. Whether it’s creating too many content types, not enough, or recreating site columns that are already available out of the box, it is critical to remember some key aspects when instituting and managing these items:
Content types are a core organizational feature of SharePoint 2010. They are designed to give users the ability to organize SharePoint content in a centralized and meaningful manner. Site columns (metadata) can be encapsulated within a content type to allow for reusable structure or independently added to sites and lists.
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