Simplify the following text for a Grade 4 native English-speaking person.
Original: Ando began the sales of his most famous product , Cup Noodle ( Kappu NÅ `` doru on September 18 , 1971 with the masterstroke of providing a waterproof polystyrene container .
Simplified: Ando began sales of the Cup noodles on September 18 , 1971 .