The document discusses different operating system structures including monolithic kernels, microkernels, and layered architectures. It also describes key components of a computer system such as users, application programs, system programs, the operating system, and hardware. Additionally, it outlines several operating system models like virtual machines, client-server, exokernel, hybrid models, and clustered/distributed systems.

1. Operating System Structure
Dr. Gowthami V

2. Operating System Structure
Monolithic Kernel
• all operating system services and functions are bundled together in a
single large executable.
Microkernel:
• It follows a minimalist approach, where only essential functions like
process management, memory management, and inter-process
communication (IPC) reside in the kernel.

3. • Layered Architecture:
• The operating system is divided into layers, where each layer provides
specific functionality.

5. A Computer System consists of:
• Users (people who are using the computer)
• Application Programs (Compilers, Databases, Games, Video player,
Browsers, etc.)
• System Programs (Shells, Editors, Compilers, etc.)
• Operating System ( A special program which acts as an interface
between user and hardware )
• Hardware ( CPU, Disks, Memory, etc)

6. Virtual Machine (VM):
• To create and manage multiple virtual machines on a single physical
machine.
• Each virtual machine runs its own operating system instance, enabling
better isolation and resource utilization for different tasks .

7. • Client-Server Model:
• It is a collection of services that can be accessed remotely.
• Clients request services from servers, which provide the necessary
functionality.
• Exokernel:
• It provides a minimalistic interface to applications and delegates
resource management tasks, such as memory and hardware control,
to user-level programs.

8. • Hybrid Models:
• It use hybrid structures that combine elements from different models.
• Object-Oriented Design:
• components are modeled as objects with associated data and
methods.
• This design promotes reusability, extensibility, and encapsulation.

9. • Clustered System:
• Multiple machines are interconnected to work together as a single
system.
• Distributed System:
• Multiple interconnected computers collaborate to provide a unified
computing environment.