What is a square inch?

Answer 1

A square inch is a unit of measurement of an area. It is the area contained in a square, the four sides of which are each exactly one inch long. But an area containing one square inch does not have to be square, or even four-sided. It could be a circle, a triangle, a rectangle, a pentagon, an irregular polygon, or even a 'blob.' The only issue is the area contained in the figure. A Note on Terminology: There is a difference between 'one square inch' and 'one inch square.' Although the area is the same, the shape in the latter is indeed a square -- a square measuring one inch on each side. 'Two square inches' is definitely different from 'two inches square.' 'Two inches square' is a square measuring two inches on each side. A square measuring two inches on each side contains four square inches.