A rectangle is a two-dimensional closed figure with four sides and four right angles. The word rectangle can in fact be broken into two words: rect and angle.
The word rect comes from the Latin word rectus meaning right or straight. The word rectangle therefore is referring to the fact that the rectangle must have a right angle. The following figure is a rectangle.
Opposite sides are parallel
Opposite sides are equal
Each of the interior angle is equal to 90 degrees
The sum of all interior angles is 360 degrees.