1. Why Operating System is needed? Provide 3 reasons.
The OS provides a common set of services and methods to access the hardware and other
resources of the computer which must be shared in a coordinated way between
applications.
I.
II.
III.
OS manages the computer memory and processes.
Coordination and assignment of compilers, interpreters, assemblers and other
software to the various users of the computer systems.
Keeping track of time and resources used by various jobs and users.
2. Draw 4 layer architecture of an Operating System & explain each
layer briefly.
KERNEL
SHELL
HARDWARE
1. HARDWARE - The hardware consists of the memory, CPU, arithmeticlogic unit, various bulk storage devices, I/O, peripheral devices and other
physical devices.
2. KERNEL
- This is a bridge between applications and the actual data
processing done at the hardware level.
3. SHELL
- Shells incorporate a programming language to control
processes and files, as well as to start and control other programs.
4. GUI
- Graphical user interfaces would become the standard of
user-centered design in software application programming, providing
users the capability to intuitively operate computers and other
electronic devices.
3. Name 5 Computing Environments & explain 3 of them
briefly.
1.
2.
3.
4.
5.
Personal Computing Environment
Time Sharing Computing Environment
Client Server Computing Environment
Distributed Computing Environment
Cloud Computing Environment
 Personal Computing Environment - In the personal computing environment,
there is a single computer system. All the system processes are available on the
computer and executed there.
 Time Sharing Computing Environment - The time sharing computing
environment allows multiple users to share the system simultaneously.
 Client Server Computing Environment - In client server computing, the client
requests a resource and the server provides that resource. A server may serve
multiple clients at the same time.