What is defined as any non-natural structure built on or affixed to land?

The term 'Improvements' in the context of real estate refers to any non-natural structure that has been constructed or affixed to land. This includes buildings, roads, sidewalks, and any other man-made enhancements that add value to the property. Improvements are significant in real estate as they can increase the property's overall worth and utility, making them crucial for property assessments and transactions.

In contrast, fixtures are typically considered items that were once personal property but have become part of the real estate because they are attached in some way, such as lighting fixtures or built-in appliances. Attachments and developments also relate to structures but are not as broadly defined as improvements. Attachments might refer specifically to items that are attached to a structure, while developments usually refer to the overall process of developing land, which encompasses improvements but is more about the actions taken rather than the structures themselves.

Therefore, 'Improvements' is the most accurate and comprehensive term to describe any man-made structure built on or affixed to land.