This plan of the Fitzrovia area in London was drawn by Charles Goad in 1886. It was made for a very specific purpose - to assess the risk posed by fire. The greater the risk, the greater the insurance premiums that would have to be paid.

You can see how the plan identifies who owned properties and what they were used for. It also shows what material they were built from. Even the width of the street is noted.

The whole map is then colour-coded (key not shown on map):
red = brick buildings, yellow = wooden buildings, dark blue = stone buildings, light blue = low level skylights, purple = high level skylights.

This map is just one from a set of several volumes covering most of the City of London.