Explain It Like I'm 5
Hardware
Hardware simplified
What Is Hardware?
Hardware is your computer, the HDD you're booting from, any physical technology device
Think of hardware as a vehicle and software as the driver, it tells the hardware what to do (based on the hardware's rules)
A CPU can't do everything the software wants, it has a set of instructions it can do and the software needs to plan the path to it's destination based on the steps the CPU can
The same way that a driver needs to plan the trip's route in order to get to his destination based on the vehicle's limitations
IE: A car is not allowed to go through sidewalk, not allowed to run a red light and can't go through stairs -> Now the driver needs to plan his route according to these limitations