Most locations will be on the main island of Taiwan. Note that there are a various small islands which are also part of Taiwan: Kinmen County, Penghu County, Green Island, Orchid Island, and Lienchiang County. All these areas are also covered by Google Street View.
Taiwan uses a multi-tier system to label their roads.
National highways are the highest tier. They are labelled using numbers 1-10. On road signs, they are depicted using a figure of a plum blossom (the national flower).
The second tier are the provincial highways. Numbers 1-39 are labelled using a blue sign. Road numbers 61-88 use a red sign with a blue border.
Roads running through counties use numbers 101-205. These are depicted on a white sign. Some road number may have 甲 (or in some cases 乙 or 丙) appended, which should be read as a (or b and c, respectively). These indicate branches of the road.
At the lowest level, there are township and district roads. These can be recognised by a prefix (a Chinese character) to indicate the region. They are generally inconvenient to use to identify a location, unless the region is known.