Video narration
On the rectangle on your page, are the edge and the inside measured the same way? Keep your finger on the rectangle's border and trace it all the way around. That distance is perimeter. Add every side: four plus three plus four plus three is fourteen units. Those are length units because you're measuring a line. Now look inside that same rectangle. Imagine coloring it in. Area is the flat space the shape covers, not the length of its boundary. The same rectangle has two different measurements: one follows its edge, and one covers its inside. If the rectangle is four units long and three units wide, multiply four by three. That gives twelve square units of colored space. So, are they measured the same way? No. On your paper rectangle, the edge is perimeter; the space you can color is area.