Constructor

first of all I will try to simplify it, using somethings that childrens like.

I will choose the example of choclat,and I will buy for him some choclat and tell him about the source of it,he will answer ,from seller
,then Iwill add other question and the seller bringued it from where? he will answer by I don’t know,then I will add by saying that the the constractor is the main source of choclat that do the instruction of preparing for us choclat without seeing it