An operating system (OS) manages all other applications and programs in a
computer, and it is loaded into the computer by a boot program. It enables
applications to interact with a computer’s hardware. Through a designated
application programmer interface, the application Programmers request services
from the (OS) (API). The kernel is the software that contains the
operating system’s core components. To run other programs, every computer
has to have at least one operating system installed

Windows, Linux, and Android are examples of operating systems that
enable the user to use programs like MS Office, Notepad, and games
on the computer or mobile phone. It is necessary to have at least one
operating system installed in the computer to run basic programs like
browsers.

The core functions of an operating system

include:

• Managing hardware resources: An operating system manages resources such as CPU, memory, and disk space, and assigns these resources to running applications.
• Running applications: An operating system provides an environment in which applications can run and interact with the user.
• Providing a user interface: An(OS) provides a graphical use interface (GUI) that allows users to interact with the computer.
• Examples of popular operating systems include:
• Windows: Microsoft Windows is the most popular desktop operating system, used by over 1 billion users worldwide. It has a wide range of features and applications, including the Office suite, gaming, and productivity tools.
• Mac OS: Mac OS is the desktop operating system used by AppleMac computers. It is known for its clean, user-friendly interface, and is popular among creative professionals.
• Linux: Linux is an open-source operating system that is available for free and can be customized to meet specific needs. It is used by developers and businesses, as well as individuals who prefer an
  open-source, customizable operating system

History of Operating Systems

The first computer, Z1, was made in 1936 – 1938. Unfortunately, this
computer ran without an operating system.

• The first computer, Z1, was made in 1936 – 1938. Unfortunately, this
• computer ran without an operating system.
• Twenty years later, the first-ever operating system was made in 1956.
• In the 1960s, Bell Labs started working on building UNIX, the first
  multitasking operating system.
• In 1977 the Apple series came into existence. Apple Dos 3.3 was the
  first disk operating system.
• In 1981, Microsoft built the first operating system called DOS by
  purchasing 86 – DOS software from a Seattle company
• The most famous Microsoft Windows came into existence in 1985
  when MS-DOS was paired with GUI, a graphics environment.

Functions of Operating System

• Processor Management: An operating system manages the processor’s work by allocating various jobs to it and ensuring that
  each process receives enough time from the processor to function
  properly
• Memory Management: An operating system manages the allocation
  and deal location of the memory to various processes and ensures
  that the other process does not consume the memory allocated to
  one process.
• Device Management: There are various input and output devices.
  An OS controls the working of these input-output devices. It receives
  the requests from these devices, performs a specific task, and
  communicates back to the requesting process.
• File Management: An operating system keeps track of information
  regarding the creation, deletion, transfer, copy, and storage of files in
  an organized way. It also maintains the integrity of the data stored in
  these files, including the file directory structure, by protecting against
  unauthorized access.
• Security: The operating system provides various techniques which
  assure the integrity and confidentiality of user data. The following security
  measures are used to protect user data:Protection against unauthorized access through login.
  
• Protection against intrusion by keeping Firewall active.
• Protecting the system memory against malicious access.
• Displaying messages related to system vulnerabilities.
• Error Detection: From time to time, the operating system checks the
  system for any external threat or malicious software activity. It also
  checks the hardware for any type of damage. This process displays
  several alerts to the user so that the appropriate action can be taken
  against any damage caused to the system.
• Job Scheduling: In a multitasking OS where multiple programs run
  simultaneously, the operating system determines which applications

Features of Operating Systems

Here is a list of some important features of operating systems:

1. Provides a platform for running applications
2. Handles memory management and CPU scheduling
3. Provides file system abstraction
4. Provides networking support
5. Provides security features
6. Provides user interface
7. Provides utilities and system services
8. Supports application development

Components of Operating System

• Now to perform the functions mentioned above, the operating system has two components:
• Shell
• Kernel

What is Kernel

The kernel is the core component of an operating system for a
computer (OS). All other components of the OS rely on the core
to supply them with essential services. serves as the primary
interface between the OS and the hardware and aids in the
control of devices, networking, file systems, and process and
memory management.

Functions of kernel

The kernel is the core component of an operating system which acts as an
interface between applications, and the data is processed at the hardware
level.
When an OS is loaded into memory, the kernel is loaded first and remains
in memory until the OS is shut down. After that, the kernel provides and
manages the computer resources and allows other programs to run and
use these resources. The kernel also sets up the memory address space
for applications, loads the files with application code into memory, and sets
up the execution stack for programs

• The kernel is responsible for performing the following tasks:
• Input-Output management
• Memory Management
• Process Management for application execution.
• Device Management

Types of Kernel

Lanus Thorvaldsen introduced the concept of a monolithic kernel in 1991
as a part of the Linux kernel. A monolithic kernel is a single large program
that contains all operating system components. However, the Linux kernel
evolved over the years and now consists of different types of kernels, as
listed below.

1. Monolithic Kernel As the name suggests, a monolithic kernel is a single
   large program that contains all components. The entire
   kernel executes in the processor’s privileged mode and provides full access
   to the system’s hardware. Monolithic kernels are faster than microkernels
   because they don’t have the overhead of message passing. This type of
   kernel is generally used in embedded systems and real-time operating
   systems.
2. Microkernel A microkernel is a kernel that contains only the essential
   components required for the basic functioning All
   other components are removed from the kernel and implemented as user-
   space processes. The microkernel approach provides better modularity,
   flexibility, and extensibility. It is also more stable and secure than monolithic
   kernels
3. .Hybrid Kernel A hybrid kernel is a kernel that combines the best features
   of both monolithic kernels and microkernels. It contains a small microkernel
   that provides the essential components for the basic functioning of the OS.
   The remaining components are implemented as user-space processes or
   as loadable kernel modules. This approach provides the best of both
   

Types of Operating Systems

There are several different types of operating systems present. In this section, we will
discuss the advantages and disadvantages of these types of OS.

• Batch OS
• Distributed OS
• Multitasking OS
• Network OS
• Real-OS
• Mobile OS

Batch OS

Batch OS is the first for second-generation computers.
This OS does not directly interact with the computer. Instead, an operator
takes up similar jobs and groups them into a batch, and then these
batches are executed one by one based on the first-come, first, serve
principle

Advantages of Batch OS

• Execution time taken for similar jobs is higher.
• Multiple users can share batch systems.
• Managing large works becomes easy in batch systems.
• The idle time for a single batch is much less