What are properties of a rectangle?

A rectangle has four sides and four angles.

A rectangle is a closed shape.

All four angles of a rectangle are right angles. That is, they are 90 degrees.

Opposite sides of a rectangle are the same length.

Opposite sides of a rectangle are parallel. That is, if they were extended infinitely they wouldn't touch.

***Additionally, the diagonals of a rectangle are congruent (unlike other parallelograms), and they also bisect each other. While all parallelograms share the bisecting diagonals characteristic, only rectangles (and by extension squares) have congruent diagonals.***