When the program starts, what does the operating system do 15

The operating system has made the program's belly bigger, and it refuses to give money**...

Load all your startup items.

The operating system boot process is simply divided into four parts, from BIOS self-test, system boot, boot kernel, and system initialization. Each part is divided into multiple self-parts, and the establishment of an operating system is a relatively complex matter. The following describes the operating system boot process based on the version as follows.

1. BIOS self-test

When the computer is turned on, Boot is automatically executed, directing the CPU to transfer the operating system from mass memory to the volatile zone of the main memory. The function of the BIOS consists of two parts, which are the POST code and the runtime service. Once the POST phase is complete, it will be purged from memory, and the runtime service will be retained for boot of the target operating system.

2. System guidance

The core job of the bootloader is to read the Linux kernel from external memory into memory and put it in the appropriate place. The kernel of Linux is divided into three parts, the main part is the kernel image running in protected mode or 64-bit to be compressed, and there is a decompression program before the kernel image to decompress the kernel file header is a real-mode initializer for running in protected mode.

3. Start the kernel

When the processor leaves the bootloader, it is in real mode, and you need to execute the bootloader in real mode to jump to protected mode to decompress the kernel image. In real mode, the bootloader performs three tasks: collecting system parameters, setting up the basic environment, and switching processor operating modes.

4. Decompress the kernel

As mentioned earlier, Linux is a memory image in memory, which needs to be decompressed, and the kernel needs to be placed in the appropriate position after decompression. This location is at 0x100000 (1MB) in the old version, and the new version requires 0x1000000 (16MB) of the physical memory, which can save less than 16MB of memory space for DMA.

The first thing that the computer executes when it is turned on is the BIOS program.

The BIOS stores the most important basic I/O programs, boot self-test programs, and system auto-start programs, and reads and writes specific information about system settings from the CMOS. The BIOS interrupt service program is essentially a programmable interface between the software and the hardware in the microcomputer system, which is mainly used to realize the connection between the program software and the microcomputer hardware.

System bootloader, Liunx bootloader is a GRUB bootloader, Windows is NTLDR

The boot process of the Windows operating system usually includes the following steps:

Power-on self-test (POST): When the computer is powered on, the system hardware will perform a self-test, including checking whether the memory, processor, hard disk and other hardware are operating normally.

Master Boot Record (MBR): The master boot record is stored in the first sector of the hard disk (boot sector). When the computer boots up, the BIOS loads the MBR and executes the bootloader in it.

The MBR contains a bootloader and a partition table.

Bootloader: The bootloader is loaded and executed by MBR. It is responsible for finding the boot file of the operating system during the boot process.

In the Windows operating system, a commonly used bootloader is NTLDR (Windows XP and earlier) or Windows Boot Manager (Windows Vista and later).

Operating system loading: The bootloader reads the operating system boot files stored on the hard disk and passes control to the operating system kernel. The operating system kernel, such as the Windows NT kernel, is loaded into memory and begins to initialize the various components of the system.

Boot services and drivers: The operating system kernel loads and starts the necessary services and drivers to ensure that the system's functions are working properly. Clan Town.

User login: Once the operating system is initialized, the system displays a login screen and waits for the user to enter the username and password to log in. After the user logs in, the user profile is loaded and the user's working environment is prepared.

Boot Complete: Once the user logs in successfully, the OS boot process is complete and the user can start using the computer and running the application.

The boot process of the Windows operating system can be divided into the following stages:

1.BIOS loading phase: When the computer is turned on, it will first self-test the hardware and load the BIOS program. The BIOS is a program solidified on the motherboard of a computer, which is responsible for initializing the hardware, setting system parameters, and other operations.

2.Bootloader phase: After the BIOS completes the self-test, it looks for the boot device (e.g., hard disk, CD, etc.) and hands over control to the bootloader in the boot device.

3.Kernel boot phase: When the bootloader finds a bootable manipulation as the system kernel, it hands over control to the kernel and begins to cheat on the kernel**. The kernel is responsible for managing system resources, providing system services, and drivers.

4.User mode startup phase: After the kernel is executed, it will jump to user mode, where the system will load some necessary drivers and services and prepare for the user login interface.

5.User login phase: When the user enters the correct username and password, the system verifies the identity and enters the desktop environment.

The above is the basic boot process of the Windows operating system, and the specific details may vary slightly due to different hardware configurations, operating system versions, and other factors.

The operating system of the computer should be called the 'operating program' to be precise

An operating system is a type of system software.

System software refers to the system that controls and coordinates computers and external devices, supports the development and operation of application software, and is a collection of various programs without user intervention, and its main function is to schedule, monitor and maintain computer systems; Responsible for managing the various independent pieces of hardware in a computer system so that they can work in harmony.

The most important and basic thing in computer software is the operating system. It is the lowest level of software, which controls the programs running on all computers and manages the resources of the entire computer, and is the bridge between the bare metal of the computer and the applications and users.

What do you mean? Press F12 to enter the boot option when starting.

Or go to the BIOS settings to modify the startup items.

1. The operating system is the software foundation of the computer. It forms the system with the hardware of the computer. Enabling computers to work for humans.

2. All applications are installed in the operating system, and the operating system is a basic software.

3. Use a simple analogy to illustrate the relationship between operating systems, computer hardware, and application software: computer hardware is equivalent to land, operating systems are like clear water houses on land, and application software is like furniture, people, and water pipes in the house. The air pipes, electrical wiring, exterior wall color and other ancillary facilities are the same.

It's all about making better use of a good house.

4. At the same time, different applications require different tools, such as water and electricity for cooking, TV, radio and so on for entertainment; In the computer, different application software is needed to complete different work, photoshop, autocad, word for word processing, and excel for electronic **.

No, system programs are part of the operating system.

The operating system of the computer should be called the 'operating program' to be precise