area-the amount of space that a 2 dimensional figure takes up
perimeter- the length of the outer edge of a 2 dimensional figure or in other words the length of all sides added up
for area i guess if you were going to build a stop sign you need to know the area of the shape so you know how much metal you need
for perimeter you may need to find the perimeter of a lake to be able to put a walkway around it so you need to know how much sidewalk you need