A townhouse is like a house in that the owner owns both the structure and the land on which it sits; but it is not free standing, so "the land on which it sits" is limited to the front and back yards. Townhouses are connected to one another in a row, and are usually two or three stories tall. They share many of the characteristics of condominiums.
Like townhouses, condominiums are attached to one another. If you own a condo, you do not own the land surrounding your living space. A condo owner owns only the unit itself, which is taxed as an individual entity, and sometimes a percentage of the common areas of the community. Condo communities may provide such shared facilities as a pool, gym, tennis courts and clubhouse, all maintained by the condo association, which takes care of all day-to-day management tasks. This is one of the key advantages of condo living...all the joy of using the amenities, none of the hassles of maintaining them. Condominium owners pay a monthly fee to the condo association, which also sets the rules for the community.