Real estate, usually residential real estate, that one purchases with the intent of earning from it. That is, investment real estate is real estate purchased with the intent of renting it, selling at a higher price, or using for almost any purpose other than using it as a residence. Common examples include apartment buildings and second houses. Investment real estate is often taxed differently from other real property. For example, one may not be able to deduct the interest paid on an investment real estate mortgage.
(source: http://financial-dictionary.thefreedictionary.com/Investment+Real+Estate)