In the story ‘Ali Baba and the Forty Thieves’ Ali Baba watches as the captain of the thieves stands before a wall of rocks and says, ‘Open Sesame!’.

This magic saying opens a door in the rocks that allows the thieves to enter a cave where an immense treasure is hidden. 

In Arabic this magic saying is iftaH ya simsim

What follows here will also ‘open a door’ in your understanding of Arabic.