If you had an ancestor who lived in Brockton, Massachusetts at one point or another and are trying to find out more information on them, a good place to go for information would be the "Brockton Poll Taxes" books, which can be found in the Historical Room of the Brockton Public Library.
The poll taxes date back to 1891 and are kind of like census records. They provide the address of where your ancestor was living that certain year, the ancestor's name, his or her age, occupation, and where he or she resided the previous year (sometimes an address will be provided while other times only a city is given). The poll taxes also list who else was living at the address at the time (with the exception of children).
The streets are organized by Ward and Precinct. And the streets are listed within each precinct in alphabetical order. If you don't know what ward and precinct the street you're looking for is a part of, I highly suggest scanning one of the books (it doesn't matter which year), find the streets you are looking for, and copy down the ward and precinct. That way, you can save yourself a lot of time in the future and will know where to look when searching through other books.
Due to women not being allowed to vote until 1920, only the men are listed in poll taxes prior. The first poll tax to include women is 1922.