Today April 21st in Iran is named Saadi day, But who is Saadi?
Briefly he was one of the most famous Iranian poets who lived 800 years ago but his poems are remained and in our era his books can be found in every Iranian.
Saadi in a Rose garden, from a Mughal manuscript of his work Gulistan, c. 1645. Saadi is on the right.
Even Nicolas Léonard Sadi Carnot the French scientist (The father of thermodynamics) has his name Saadi.
For more information in your language you can read following articles.