Before the modern phone book, many cities and towns published alphabetical directories of their residents. These publications contain lists of names and addresses of most adults and businesses in the town. They often contain the names of husband and wife, and in some cases even include references to spouses no longer living, such as "Brown, Ellen, widow of Samuel."
Most directories list a resident's occupation and employer as well. In such cases, one could map out the commutes for the employees of a particular establishment.
Some examples of the important and unique information found in city directories are given in "The wealth of information" section below.