In co-ops you don't even own that. In a condo, you purchase the real property on the inside of the unit (from the walls in). In a co-op, you purchase shares in a corporation that owns all the real property, inside and out. None of the actual real estate is yours, only part ownership in a corp that owns it. The board my allow you to install a dish inside, but y0u'd may well have to ask permission first.
In the case of condominiums, cooperatives and rental properties, the rules apply to “exclusive use” areas, like terraces, balconies or patios. “Exclusive use” refers to an area of the property that only renters and their guests may enter and use