If you are wondering if you are looking at a condominium, or a townhouse, it may not always be so obvious: many condominiums do look like townhouses, with 2 stories and even a real enclosed garage attached (as it is the case in this complex: the Old Mill in Mountain View).
A condominium is a unit inside of a larger complex, where the owner owns a small part of the whole
complex. It is also said that in a condominium, you own "from the paint on", meaning that the rest is owned in common. For instance if there are 100 units, you would own 100th of the whole property; many times it includes several buildings, the land, the pools etc... So in a way you do not really own where you live, you own a portion of a much larger property. Of course you have exclusive use of your location, and also the exclusive use of a parking space, a balcony, a storage area. The legal description (shown in the preliminary title report) indicates that it is a condominium.
In the case of a townhouse, you own the land you are on, and the house which is on it, and typically you are responsible for the maintenance of the whole place: you have to pay to repair or change your own roof, you have to paint the home, you take care of your own stucco, garden, fences etc... If you have rules that limit what you can do, it would be because of the association that regroups all the townhomes around you, which might be responsible for the walkways, the access roads, the common facilities (pool, tennis etc...). Those rules help keep a common look and living experience to all the homes inside the complex.
In many areas, especially where there is very little land to build on (think "the Bay Area"), the exact definitions get blurred, and you can have homes that may look like townhouses but are in fact condominiums. So be careful and ask your agent to double check on that for you (in the preliminary title report).
Even though it is always good to "own your own land", lifestyles change, and many buyers prefer that an association take care of the roof, fences, pools, paint, and so on. A condo can be better for that. The "association dues" are meant to be used for those repairs, and often a management company takes care of them.
I had written a blog in 2010 on the subject of condominiums, with some other detailed explanations, which you may be interested in checking out ....
Thank you for reading,