For the purposes set forth in MGL c. 40A and all acts in amendment thereof and in addition thereto and under the authority thereof, the height, area, location and use of buildings and structures and the use of land throughout the Town of Westminster is hereby regulated as provided herein, and the Town is hereby divided into districts as hereinafter designated, defined and described and shown on an official copy of the Zoning Map, dated March 27, 1974, as amended, on file with the Town Clerk, which map is hereby made a part of this chapter.