Hi ! I had read a lot of book and link about initialization of the boot starting of linux. I read that , after the post by the bios the mbr is loaded in memory which routine load this sector ? In this sector of 512 bytes we have 440 bytes for a routine what is the function of this routine ? When this routine is executed ? The 2 bytes with 0xAA55 what is its function ? Who load it in memory ? And the all book i had read said the mbr load the loader grub How ? And the grub launch the kernel, ok . How this grub is load ? By which programm ? So, i would like that someone give me the names of routines, the order of their launching and which load or execute what until the grub exécution ? Thank you for your help. Greg i am waiting a lot from you ! Best regards Gnoleba GNOGBO