Chapter 1 – Introduction to OS
What is an Operating System?
•Operating System is a Resource Manager.
•Handles multiple computer resources: CPU,
Internal/External memory, Processes, Tasks,
Applications, Users, etc…
•Manages and allocates resources to multiple
users or multiple jobs running at the same time
(e.g., processor time, memory space, I/O
devices)
•Arranges to use the computer hardware in an
efficient manner (maximize throughput,
minimize response time) and in a fair manner.
• It is a Control Program.
• Manages all the components of a complex
computer system in an integrated manner.
• Controls the execution of user programs and I/
O devices to prevent errors and improper use
of the computer resources.
• Looks over and protects the computer.
• It is an extended/virtual machine
• An interface between the user and hardware
that hides the details of the hardware (e.g., I/O).
• Constructs higher-level (virtual) resources out
of lower-level (physical) resources (e.g., files).
•Definition: Is a collection of software
enhancements, executed on the bare
hardware, culminating in a high-level virtual
machine that serves as an advanced
programming environment
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Prepared by Dr. Amjad Mahmood
