What is an operating system?
An operating system, or “OS,” is software that communicates with the hardware and allows other programs to run. … Every desktop computer, tablet, and smartphone includes an operating system that provides basic functionality for the device. Common desktop operating systems include Windows, OS X, and Linux.
An Operating System (OS) is a software that acts as an interface between computer hardware components and the user. Every computer system must have at least one operating system to run other programs. Applications like Browsers, MS Office, Notepad Games, etc., need some environment to run and perform its tasks.
The OS helps you to communicate with the computer without knowing how to speak the computer’s language. It is not possible for the user to use any computer or mobile device without having an operating system.
Types of Operating System (OS)
Following are the popular types of Operating System:
- Batch Operating System
- Multitasking/Time Sharing OS
- Multiprocessing OS
- Real Time OS
- Distributed OS
- Network OS
- Mobile OS
Batch Operating System
Some computer processes are very lengthy and time-consuming. To speed the same process, a job with a similar type of needs are batched together and run as a group.
The user of a batch operating system never directly interacts with the computer. In this type of OS, every user prepares his or her job on an offline device like a punch card and submit it to the computer operator.
Multi-Tasking/Time-sharing Operating systems
Time-sharing operating system enables people located at a different terminal(shell) to use a single computer system at the same time. The processor time (CPU) which is shared among multiple users is termed as time sharing.
Real time OS
A real time operating system time interval to process and respond to inputs is very small. Examples: Military Software Systems, Space Software Systems are the Real time OS example.
Distributed Operating System
Distributed systems use many processors located in different machines to provide very fast computation to its users.
Network Operating System
Network Operating System runs on a server. It provides the capability to serve to manage data, user, groups, security, application, and other networking functions.
Mobile OS
Mobile operating systems are those OS which is especially that are designed to power smartphones, tablets, and wearables devices.
Some most famous mobile operating systems are Android and iOS, but others include BlackBerry, Web, and watchOS.
The “missing operating system” or “operating system not found” error message usually appears on a black window when you start your Windows computers. This error is very common for Dell, Acer, Lenovo, HP and Sony desktops and laptops. When your Windows 10/8/7/XP/Vista operating system not found on its boot drive, it’s impossible to start the computer until the operating system is restored. You can read on to get error details or directly jump to comprehensive solutions.
Functions of Operating System
Below are the main functions of Operating System:
In an operating system software performs each of the function:
- Process management:- Process management helps OS to create and delete processes. It also provides mechanisms for synchronization and communication among processes.
- Memory management:- Memory management module performs the task of allocation and de-allocation of memory space to programs in need of this resources.
- File management:- It manages all the file-related activities such as organization storage, retrieval, naming, sharing, and protection of files.
- Device Management: Device management keeps tracks of all devices. This module also responsible for this task is known as the I/O controller. It also performs the task of allocation and de-allocation of the devices.
- I/O System Management: One of the main objects of any OS is to hide the peculiarities of that hardware devices from the user.
- Secondary-Storage Management: Systems have several levels of storage which includes primary storage, secondary storage, and cache storage. Instructions and data must be stored in primary storage or cache so that a running program can reference it.
- Security:- Security module protects the data and information of a computer system against malware threat and authorized access.
- Command interpretation: This module is interpreting commands given by the and acting system resources to process that commands.
- Networking: A distributed system is a group of processors which do not share memory, hardware devices, or a clock. The processors communicate with one another through the network.
- Job accounting: Keeping track of time & resource used by various job and users.
- Communication management: Coordination and assignment of compilers, interpreters, and another software resource of the various users of the computer systems.
Features of Operating System (OS)
Here is a list important features of OS:
- Protected and supervisor mode
- Allows disk access and file systems Device drivers Networking Security
- Program Execution
- Memory management Virtual Memory Multitasking
- Handling I/O operations
- Manipulation of the file system
- Error Detection and handling
- Resource allocation
- Information and Resource Protection
Advantage of using Operating System
- Allows you to hide details of hardware by creating an abstraction
- Easy to use with a GUI
- Offers an environment in which a user may execute programs/applications
- The operating system must make sure that the computer system convenient to use
- Operating System acts as an intermediary among applications and the hardware components
- It provides the computer system resources with easy to use format
- Acts as an intermediator between all hardware’s and software’s of the system
Disadvantages of using Operating System
- If any issue occurs in OS, you may lose all the contents which have been stored in your system
- Operating system’s software is quite expensive for small size organization which adds burden on them. Example Windows
- It is never entirely secure as a threat can occur at any time
CAUSES OF MISSING OPERATING SYSTEM ERROR
This issue may occur if one or more of the following conditions are true:
- The basic input/output system (BIOS) does not detect the hard disk.
- The hard disk is damaged.
- Sector 0 of the physical hard disk drive has an incorrect or malformed master boot record (MBR).
Note Some third-party programs or disk corruption can damage an MBR. - An incompatible partition is marked as Active.
- A partition that contains the MBR is no longer active.
Solution A 1: Check if the hard drive is detected by BIOS
Step 1: Press and hold “F12/F10″ while pressing the “Power” button to turn on the PC.
Step 2: Release F12/F10 when the BIOS Setup Utility is displayed.
Step 3: Try to find IDE Primary Master, IDE Primary Slave, IDE Secondary Master and check whether they can be detected or not.
If no disk is shown or displayed as None/Not Detected, it means that the BIOS doesn’t detect the drive and you may select None to Auto. This may solve OS not found error.
If the system disk information is displayed, it means that BIOS can detect the hard drive and you need exit BIOS.
Solution B : Test hard disk drive and reboot computer from a WinPE bootable disk
Step 1: Press and hold “F10” and press the “Power” button to turn on PC > Release F10 after the PC screen display you with test
Step 2: Use Right Arrow to select the “Tools” menu in BIOS Setup Utility
Step 3: Then select “Hard Drive Self Test” > Press “Enter” to start the test
If all tests pass, the hard drive is not damaged. You may jump to Solution 3 to reset BIOS to default state.This will help you and windows will be installed successfully.
I hope you enjoyed this write up and your problems are solved
