It depends on the context of the question.
Regarding taxes, they are taxed the same way real estate taxes are. Mobile homes are assessed and taxed just like real estate taxes are in Indiana. The annual taxes are due twice a year, spring and fall. The county assessor assesses the mobile home and a percentage of the value is due in tax each year. The mobile home owners can also apply for a homestead exemption if they live in and own the mobile home. This cuts way down on the tax.
Regarding how they "titled", they are titles just like cars, or "personal property". However cars are taxed upon each time the car is bought or sold. This is not the case with mobile homes. The real estate taxes with the county have to be paid up to transfer the mobile home title initially.
What I believe Jhutson is refering to is used if a mobile home is on actual land, you have the choice to keep it "titled" like a car or actually "retire" the title and have it attached the land and become part of the real esate. However this cannot be done in a typical park. The homes just stay titled as a car is, and taxed like real estate is.