What happens when the computer is switched on: download phases and start of the operating system

Every time we turn on the computer, there are a number of processes with which many of us may be less familiar. These stages of downloading and launching the operating system are important points that ensure the operation of the device and enable us to use the computer to carry out various tasks.

The first phase of the computer is the implementation of POST (Power-On Self-Test) or the testing of the computer by itself. During this step, the computer checks whether all internal components, such as processor, memory and hard drive, operate. If problems are detected during POST, a computer can give a sound signal or show a message on the screen with information on the problem.

After successful completion of POST, the computer moves to the next phase, which is called initialization or downloading of BIOS (Basic Input/Output System). BIOS is a small program stored in the constant memory of a computer that is responsible for initializing all devices and computer construction. It is also responsible for launching the operating system by searching and downloading the loading device or disk.

The downloading and start-up phases of the operating system are complex and important processes that provide normal computer work. Understanding these phases will help us better understand our internal computer mechanisms and possible challenges that we can face.

Computer downloads:

When the computer is switched on, several phases have been consistently implemented, allowing the operating system to be downloaded and computerized.

1. BIOS (Basic Input/Output System) First stage of downloading, during which the computer is initialized. BIOS checks the functionality of the main components, including processor, memory, video map, initiates hardware interfaces and self-diagnoses.
2. POST (Power-On Self Test) Second stage of downloading on which the computer system is self-tested. POST conducts the testing of the hardware components and transmits the control of the loader of the operating system if all components work correctly.
3. Transaction system loader Phase three, which launches software responsible for downloading the operating system. The loader is located on a certain disc area and provides information on the location and configuration of the operating system.
4. Initiation of the operating system kernel Phase four, which initiates the nucleus of the operating system. The operating system core launches the necessary driveways and modules, develops systemic resources such as memory and file systems.
5. Entry into the operating system Phase 5, which moves to the operating system. After loading the kernel, the graphical interface or command line shall be started and the user shall be given the opportunity to inject.

Once all the loading phases have been completed, the computer is ready to work with the user and perform all the necessary tasks.

BIOS machine verification and initialization

A number of steps are being taken when the computer is switched on, which are being carried out consistently. One of the first steps is verification of the hardware and initialization of BIOS (Basic Input/Output System).

BIOS is a set of policy directives written in a microschem on a computer's mall. The main function of BIOS is to ensure that the operating system interfaces with computer equipment.

Verification of the hardware and initialization of BIOS include the following steps:

1. Processor launch. The computer receives a signal from the switch button and starts feeding the processor. The processor then begins to carry out the BIOS commands assigned to it.
2. Consistent launch of hard drives, optical drives and other peripheral devices. BIOS checks the presence and proper connection of devices, initiates them and loads the necessary information for their operation.
3. Operational memory test (RAM). BIOS checks the operational capacity and the volume of operational memory available.
4. Verification of the integrity and configuration of other hardware components, such as video maps, audible map, a web map and others. BIOS compares information on connected devices with its stored database and performs the necessary construction and installation.
5. Determination of the device from which the operating system will be downloaded. BIOS checks the presence of connected information carriers (e.g. hard drives, flash drives or CD/DVD) and determines the highest priority for downloading.

After all the steps listed, BIOS transmits the operating system management, which is already in the process of launching and starting its work.

A well-designed and relevant BIOS program is an important aspect for the stable operation of the computer. It enables the operational system to engage correctly with the hardware components and ensures their correct operation.

Loading MBR and searching for an active section

MBR (Master Boot Record) is the first hard drive sector, which provides information on disk sections and the code required to download the operating system.

When using the BIOS computer (Basic Input/Output System), the presence of MBR in the first disk sector is verified. If MBR is found, it will be loaded in operational memory (RAM).

After MBR is loaded, BIOS transmits the code control located in MBR. This code is called a loader.

The loader reads information from MBR on disk sections and finds an active section containing an operating system to be downloaded.

In order to find an active section, the loader shall refer to the table of sections which is also located in the first disk sector after MBR.

Once an active section has been found, the loader is transferring the operating system code to operational memory and transferring the code management.

Thus, the process of downloading the operating system begins with the loading of MBR, the search for an active section and the transmission of the operating system code control.

Loading of operating system loader

The downloading of the operating system is a complex and multi-stage process starting from the moment the computer is switched on. One of the most important stages of downloading is the downloading of the operator.

The downloader of the operating system is a special program that is on the hard drive of the computer and is responsible for running the operating system itself. He's uploading before the operating system itself and letting her start.

The loader is normally located in the first hard drive sector, which is called MBR (Master Boot Record) or the primary loading sector. The loading begins with the reading of MBR in computer memory and the transfer of control to the loader of the operating system.

The operator has several main tasks:

1. Search and download the files needed to launch the operating system.
2. Loading and execution of the operating system nucleus.
3. Load management and launch setting.
4. To ensure that the operating system is selected if several operating systems are installed on the computer.

The downloader of the operating system may also provide the user with the opportunity to select the loading mode, perform the diagnostics of the system, restore the integrity of the operating system and other additional functions.

The downloading of the operating system loader is an important phase of the computer launch and its successful implementation enables the downloading process to continue and the operational system to be started.

Loading of the operating system kernel

Loading the nucleus of the operating system is one of the main steps that occur when the computer is switched on. It consists of several sub-stages, including loading of the nucleus itself and loading of various modules and drivers.

Once the computer receives food, the processor starts to implement the code from the BIOS special chip (Basic Input/Output System). BIOS first checks the operation of the equipment and searches for a loading device from which the operating system can be downloaded.

After BIOS finds a loading device (usually a rigid disc), it loads the first loading device sector with a code called MBR (Master Boot Record). The MBR code is stored in computer memory and is being performed. MBR then finds and loads the second phase of the downloader, which is called GRUB (GRand Unified Bootloader), if the computer operates under the control of the Linux family operating systems, or NTLDR (NT Loader), if the computer operates under Windows operating systems.

GRUB or NTLDR then display the list of operating systems installed on the computer on the screen and provide the user with a choice by which an operating system that the user wants to download can be selected.

Once the user selects the operating system, the nucleus of the operating system is stored in the memory of the computer and started to be performed. The operating system core is responsible for managing all computer resources, including processor, memory and external devices.

The uploading of the nucleus of the operating system is therefore one of the most important stages of downloading the computer, as it enables the operating system to interact with the equipment and start its work.

Initiation and launch of system services and drivers

With the completion of the ELV and downloading processes, the initialization and launch of systems services and driveways begins. This phase consists of several sub-phases:

1. BIOS POST Power-On Self Test. BIOS (Basic Input/Output System) performs a short check of computer equipment, including memory, processor, hard drives and other devices. If the test has been successful, BIOS is transferring control to the operator of the operating system.
2. Transaction system loader Software (e.g. GRUB or NTLDR) which loads the operating system into the operational memory of the computer. The loader lies in a special section of the hard drive and provides information on how to download the operating system.
3. Initiation of the operating system kernel When the loader transmits the operating system control, the initialization of the nucleus begins. The nucleus of the operating system is the main part of the software that handles computer hardware and manages resources.
4. Loading of systems services After initializing the nucleus, the operating system is starting to download system services that are responsible for managing various aspects of the computer. For example, network services, security services, file access services and other services.
5. Driver launch Once the system is downloaded, the operating system is starting to download and start a device drive. Drivers are software that ensures interaction between the operating system and hardware, such as video maps, audible card, printer and others.

The computer is fully loaded when all necessary system services and drivers are successfully initiated and launched.

User interface launch and operating system launch

A user interface (GUI) and an operating system are being launched during the last phase of the computer download. This phase occurs after the nucleus of the operating system is downloaded and the configuration files and system services are being processed.

The operating system starts automatically and the user is provided with a working environment. The user interface may be the end interface or command line depending on the operating system chosen.

The main element of the GUI is the desk where the tags, files and files are displayed. Using mice or keyboard, the user can select the necessary elements and start the relevant appes.

As the operating system starts, various systems services and driveways are downloaded, which provide all computer components. System services may include antiviral programs, network services, task manager and other components necessary for the normal operation of the operational system.

In addition, the operational system automatically launches various support programs and services that ensure the sustainability of programs and the ability to perform all necessary operations. For example, the operational system may launch automatic renewal services, security services and other processes necessary to ensure the safety and stability of the system.

In general, the launch of the user interface and the start of the operating system are the last phase of the computer downloading process. At the end of this phase, the user will be able to work with the computer and use all functions of the operating system.

Question-record

What's going on with the computer?

Several downloads, including POST, initialization of iron, loading of BIOS and launching of the operating system, occur when the computer is switched on.

What stages of downloading are the computer?

The computer runs several stages of downloading: initial self-testing (POST), initial iron initialization, loading BIOS, searching and downloading the operating system and initializing the driveways and services.

What is POST and why is it necessary?

POST (Power-On Self-Test) is the initial self-testing performed by the computer when activated. It checks the functionality of the main components of the computer, such as processor, memory, video map and others, and identifies possible problems or malfunctions.

How's BIOS download going?

After POST, the computer is downloaded by Basic Input/Output System (BIOS), which is on a small chip on the maternal fee. BIOS initiates iron and performs various functions, including the identification and construction of hardware, the launching of the process of loading the operating system and the verification of the integrity of system files.