Generally it's called "booting up" the system. It's also how we got the term "Rebooting". It can also be called "mounting" however this term generally applies more to specific hardware devices.
booting
A computer boot process is the procedure of starting a computer from scratch, culminating in the loading of and operating system.
Booting is the act of switching on the computer and loading the operating system. This process is referred to as cold booting
Booting is the process a computer fallows by loading all necessary files to run an operating system.
An operating system loads via the memory of a computer. The specific area that gets the operating system to load is called the boot loader.
The booting process of an operating system is the sequence of events that occurs when a computer is powered on or restarted, leading to the loading of the operating system into memory. It begins with the BIOS or UEFI firmware performing hardware checks and initializing system components, followed by locating and loading the bootloader from the designated boot device. The bootloader then loads the operating system kernel into memory, which initializes system services, drivers, and user interfaces, ultimately preparing the system for user interaction. This entire process ensures that the hardware and software are ready for operation.
operating system is not a loading, When is trun on system(press the power button). first of checked all the hardware devices,for exmple hard disk,ram,rom and etc. When the all devices dected process further. Jsb
loading
The bootstrap process is the sequence of actions that a computer system goes through when it is first turned on. It involves loading the operating system into memory and initializing the hardware components to prepare the system for use. The bootstrap process typically includes hardware diagnostics, configuration checks, and loading the necessary software components.
loading
Boot is short for "Bootstrap". It's from the aphorism to "pull one's self up by one's bootstraps." A bootstrap load was the way early computer manufacturers described the process of a computer loading its operating system.
Booting up ..! A boot process is a step by step process with which a computer loads the operating system.