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+*Concepts you may want to Google beforehand: interrupts, CPU
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+registers*
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+
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+We will improve a bit on our infinite-loop boot sector and print
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+something on the screen. We will raise an interrupt for this.
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+
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+On this example we are going to write each character of the "Hello"
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+word into the register `al` (lower part of `ax`), the bytes `0x0e`
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+into `ah` (the higher part of `ax`) and raise interrupt `0x10` which
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+tells the machine to print on screen the contents of `ax`.
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+
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+`0x0e` on `ah` is necessary to indicate tty mode.
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+
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+We will set tty mode only once though in the real world we
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+cannot be sure that the contents of `ah` are constant. Some other
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+process may run on the CPU while we are sleeping, not clean
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+up properly and leave garbage data on `ah`.
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+
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+For this example we don't need to take care of that since we are
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+the only thing running on the CPU.
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+
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+Our new boot sector looks like this:
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+```nasm
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+mov ah, 0x0e ; tty mode
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+mov al, 'H'
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+int 0x10
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+mov al, 'e'
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+int 0x10
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+mov al, 'l'
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+int 0x10
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+int 0x10 ; 'l' is still on al, remember?
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+mov al, 'o'
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+int 0x10
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+
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+jmp $ ; jump to current address = infinite loop
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+
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+; padding and magic number
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+times 510 - ($-$$) db 0
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+dw 0xaa55
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+```
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+
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+You can examine the binary data with `xxd file.bin`
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+
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+Anyway, you know the drill:
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+
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+`nasm -fbin boot_sect_hello.asm -o boot_sect_hello.bin`
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+
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+`qemu boot_sect_hello.bin`
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+
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+Your boot sector will say 'Hello' and hang on an infinite loop
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Carlos Fenollosa