Garages can be converted into most other spaces, whether you need extra living space, a new Kitchen or bathroom, or even a driveway. Entire garages can be converted into living spaces or perhaps just a part of it - leaving you with some storage space. Then by creating a doorway from your house, it could be used like any other room would be.
Interior garage space for one or two cars is typical of modern housing, and garages built since the 1950's usually have a door directly linked and connecting the garage to the interior of the house. These garages are known as an "attached garage".
To see a case study showing how a garage can be converted in to a useable living space please click on this link.