My favorite Operating System is Linux and the loading process is managed by the GRUB boot loader. GRUB is not something you would find in the ground! GRUB stands for Grand Unified Boot Loader. It allows the computer to boot one or more operating systems among other things. By default, the Linux OS is booted first if the process isn’t interrupted with a mouse click.
The second OS is Microsoft windows in most cases. To get the second OS to boot automatically I found a program which configures either OS to boot first. I downloaded it and installed it a a few computer including a clients and it works great. It’s called the GRUB customizer and runs from the graphics interface of Linux.