The extent of the map is the area that is visible in the map window. If your current extent includes the whole county, you would decrease your extent to see only 4 townships in the map window.

Items that are displayed on the map. Examples could be rivers, roads, counties, townships, parcels or many others. Features are usually the items of interest on the map.

This is a grouping of related map features. An example would be Railroads. Railroads is a layer that is located under the transportation group.

Ratio of printed size to real size. If the map scale is 1:2, items on the printed map would be 1/2 the size of what is being mapped. 6 inches on the map would represent a distance of a foot. If the map scale is 1:12, items on the printed map would be 1/12 the size of what is being mapped. 1 inch on the map would represent a distance of a foot.