The golden rectangle is a rectangle whose length divided by its width is equal to 1.618. You can find it on great masterpieces of artwork, like the Monalisa and it is derived from the observation of ratios in nature.
1) Golden rectangle refers to the golden proportion, the one we can find by dividing the lengths in a ratio where:
In the Renaissance, this was rediscovered and said to be the perfect proportion found in many other proportions. This irrational number φ =1.618... is found when we divide the length by the width of the golden rectangle.
This golden ratio can be found in artwork, and in nature like the spirals that an Italian mathematician called Fibonacci found
If we divide the length by the width of any of these rectangles, we'll find the same ratio: φ =1.618.. or