The document outlines the Class XI Computer Science curriculum focused on Python, including units on computer systems, programming, and ethical considerations. It explains fundamental concepts such as hardware, software, peripheral devices, and the CPU's role in processing instructions. Additionally, it details types of operating systems and language processors involved in programming and system functionality.

1. Computer Science with Python (083)
Class XI
Dr. Sunil Vats, PGT Computer Science

2. Computer Science with Python (083)
Class XI
Unit No. Unit Name Marks Theory Practical
1 Computer Systems and Organization 10 10 10
2 Computational Thinking and Programming-1 45 80 60
3 Society, Law and Ethics 15 20 -
Total 70 110 70

3. Computer System Overview

4. What is Computer?
Computer is a programmable electronic device that
accepts raw data as input and processes it with as
set of instructions ( a program) to produce the result
as output
C O M P U T E R
Common
Operating
Machine used for Education
Purposely Trade/Technology Research

6. Two Components of Computer
• Hardware
• Physical electronic components of a computer
• Software
• Recorded instructions and programs to govern the
working of the computer.

7. Peripherals
Devices
Input
Devices
Output
Devices
Secondary
Storage
Devices
Internal
Components
01
02
03
04 05
Hardware
Component

8. Peripheral devices are not
essential to the
functioning of a computer,
but they enhance its
functionality. These
devices can be input
devices, output devices, or
both
Peripheral devices

9. Input devices provide us a way to
give input or instruct the computer
to perform a function. It can be any
information or data given to the
processor and this processor gives
the output by some output device.
In a computer, the keyboard and
mouse are input devices,
Input devices
Keyboard
01
Mouse
02 Joystick
03
Track Ball
05 Scanner
06
Light Pen
04
Digitizer
07
Microphone
08 MICR
09
OCR
10

10. An output device is any piece of
computer hardware that converts
information or data into a human-
perceptible form or, historically, into
a physical machine-readable form
for use with other non-
computerized equipment. It can be
text, graphics, tactile, audio, or
video.
Output devices
Monitors
01
Printers
02 Headphone
03
Projectors
05 Sound Card
06
Speakers
04
Braille Reader
07
GPS
08 Video Card
09
LCD
10

11. The CPU, also referred to as the “central”
or “main” processor, is a complex set of
electronic circuitry that runs the
machine's operating system and apps.
The CPU interprets, processes and
executes instructions, most often from
the hardware and software programs
running on the device.
Central Processing Unit (CPU)

12. Central Processing Unit (CPU)
Central Processing Unit (CPU)
Arithmetic Unit
Control Unit
Register
Central Processing Unit (CPU)
Control Unit (CU)
Arithmetic & Logic Unit
Registers
Memory Unit
Input
Output

13. ALU
Control Unit (CU)
Arithmetic & Logic Unit
Registers
Memory Unit
1. Perform Arithmetic Operation
(+,-,*,/ )
2. Perform Logical Operation
( <, > , <=, >=, ==, !- )
3. Decision Making
(&&, ||, ! )
Arithmetic & Logic Unit

14. CU
Control Unit
Control and Guides the Interpretation,
flow and manipulation.
Control Unit

15. Registers
Registers
• Small Units of Data Holding Places
located near the processor.
• Used to store some important
instructions and important data when
CPU is running some program
• Frequently used Instruction/Memory
is stored in Registers and rest of the
instructions/Data is stored in Cache,
RAM etc.
Registers

16. A memory unit is a small
storage device that holds a
memory for a computer and
can be accessed through the
software. Memory units are
typically used to store the
information of the programs.
Memory
Volatile Memory Non-Volatile Memory
Memory

17. ROM FLASH

18. Computer
Memory
Primary
Memory
RAM
SRAM
DRAM
ROM
PROM
EPROM
EEPROM
Secondary
Memory
Sequential
Magnetic
Tape
Gramophone
Random
Magnetic
Disk
Hard Disk
Floppy
Disk
Optical
Disk
CD
DVD
Flash
memory
Pen Drive
Memory
Card
Computer Memory

20. System Bus Architecture
System Bus Architecture
CPU
Control Bus
Address Bus
Data Bus
Memory
Input &
Output
System
Bus
System Bus
An Electronic pathway composed of
connecting cables and that connects the
major components of a computer.
Data and instruction are passed among the
computer system components through
System Bus.
Data Bus
Carries Data
Control Bus
Carries Control Instructions
Address Bus
Carries Address

21. Software is a set of instructions, data or programs
used to operate computers and execute specific
tasks. It is the opposite of hardware, which
describes the physical aspects of a computer.
Software is a generic term used to refer to
applications, scripts and programs that run on a
device.
Software
Software
System Software Application Software
Operating System
Language Processor
General Purpose
Customize Software

22. System Software:
System software is software that directly operates the computer
hardware and provides the basic functionality to the users as well as to the
other software to operate smoothly. System software basically controls a
computer’s internal functioning and also controls hardware devices such as
monitors, printers, and storage devices, etc. It is like an interface between
hardware and user applications, it helps them to communicate with each
other because hardware understands machine language(i.e. 1 or 0) whereas
user applications are work in human-readable languages like English, Hindi,
German, etc. so system software converts the human-readable language into
machine language and vice versa.
System Software

23. Function of Operating System

24. Generation First Second Third Fourth
Year 1945-1955 1955-1965 1965-1980 Since 1980
Device Used Vacuum Tubes Transistors
Integrated Circuits
(IC)
Large Scale
Integration
Type of OS Plug Boards Batch Systems Multiprogramming PC
In 1985, Operating System Windows first came to existence when a GUI was paired with MS-
DOS.
History of Operating System

25. Type of Operating System
Batch Processing Operating System
Similar types of jobs are grouped together under a batch
which is executed without any user intervention. The jobs are there
in process in the order of submission.
Multitasking or Time Sharing Operating System
Allows many users to share the computer’s resources
simultaneously. It also reduces the CPU idle time.
Distributed Operating System
This operating system uses multiple central processes to serve
many real-time applications. The distributed operating system
manages a group of independent systems and projects them to a
single system.
Network Operating System
It runs on a server and helps manage data and other networking
functions in a system.
Real-time Operating System
Aims to execute real-time applications. The user intervention is
bare minimum and it is a time-bound operating system.

26. Language Processor
A Language Processor, or translator, is a computer program that translates source code
from one programming language to another. They also identify errors during translation.
Computer programs are usually written in high-level programming languages (like C++,
Python, and Java). Further, to make them understandable by the computer, a language
processor needs to translate the source code into machine code (also known as object
code, which is made up of ones and zeroes).