The Drag Test

The interactive construction below shows several squares constructed in different ways.

• Examine the squares by dragging ALL their vertices with the mouse.
• Find out which of the quadrilaterals are real squares and which ones just happen to look like squares.

What is the difference between a drawing and a construction?

What is the Drag Test and why is it important for interactive constructions?

Why is it important to construct figures instead of just drawing them in a Dynamic Mathematics Software?