text: ### Theory:
  
  Anything that is not straight is referred to as a curve.
  There are different types of curves. Some of which are:
  • Simple curve
  • Non-simple curve
  • Open curve
  • Closed curve
  
  A curve that does not cross itself is called a simple curve.
  
  A curve that crosses its own path is called a non-simple curve.
  
  An open curve is a curve whose endpoints do not meet at any point. It has two endpoints.
  
  A closed curve is a curve, which has no endpoints and enclosed an area.
  
  A closed curve contains $$3$$ parts. They are:
  • Interior of the curve
  • Exterior of the curve
  • Boundary of the curve
  
  1. Interior of the curve:
  
  The inside / inner region of the curve is referred to as the interior of the curve. In the above figure, point $$A$$ lies on the interior of the curve.
  
  2. Exterior of the curve:
  
  The outside / outer region of the curve referred to as the exterior of the curve. In the above figure, point $$B$$ lies on the exterior of the curve.
  
  3Boundary of the curve:
  
  The curve, which divides the interior and exterior part, is called a boundary of the curve. In the above figure, point $$C$$ lies on the boundary of the curve.
  
  Important!
  The interior and boundary of the curve together are called "the region" of the curves.