1. Basics of Computer A Computer is Electronic device that can
accept data,
store data,
process data as desired,
retrieve the stored data as and when required
print the result in desired format.
Computer consist of mostly two types of components.
These components hardware and software.

2. What is Hardware?
The stuff you can actually see and touch are Hardware.
It is a physical component of the computer system.
It is consist of a processor , input and output devices , memory , storage device.

3. Types of Hardware

4. Software and its Type
Software is a set of programs, which is designed to perform a well defined function.
A program is a sequence of instruction written to solve a particular problem.
Computer hardware would be useless without software, set of instructions which command the hardware to do the logical operation is given by software.

5. Type’s of software
System Software(Operating System )
Utility software
Applications software
System Software: It manages the computer and allows the user to communicate with the hardware.
Ex. Operating System , compiler , linker.

6. Application software::
Application software is a set of one or more programs designed to carry out operations for a specific application. Application software cannot run on itself but is dependent on system software to execute.
Examples of application software include MS Word, MS Excel, a console game, a library management system, a spreadsheet system etc.

7. Programming Language
Definition: A programming language is a special kind of instructions which is used to communicate with computer.
Types: 1. High level P.L.
2. Low level P.L.
High level P.L.::: A Programming language syntactically similar to English and easy to understand is called H.L.P.L.
Low level P.L:: This Programming language also called assembly language. In assembly language instruction will be in symbolic format and it is not that much of easy to remember.

8. Definition of ‘ C ‘ language
C is a High level , simple block structured ,procedure oriented programming language.
Basic purpose of C language was to write System software such as Operating System
Later C is used to writing System software as well application software also.

9. Structure of ‘ C ‘ language
#include<…h> …………………………….>>>Header File
void main() ……………………………….>>> Startup Function
//void is function return type, and void means return nothing
{ Starting curly bracket(starting of program
________________________;
___________ Program Body _____________;
___________________________;
} Ending curly bracket(End of program)

10. Header File
Definition: Header file is collection of programs library that contain
predefine functions code like printf , scanf in stdio.h .
.h is a header file extension.
Example:
#include<stdio.h> for printf and scanf function
#include<conio.h> For clsrscr() and getch() function
#include<math.h> For sqrt() and other maths related function.
#  Hash is preprocessor directives it means during compilation
first preprocess the file or header file.

11. Variable and Constants
Variable : A unit for which value can be change during course of program execution.
Ex: into a;//Variable Declaration
Into a=5; //Variable Initialization
a=6;
a=10; Now value of variable a will be 10.
Constant : A unit for which value cannot be change during course of program execution.
Ex: any number.

12. Flowchart and Algorithm
Flowchart: Flowchart is graphical or diagrammatical representation of sequence of any problem to be solved by computer programming language.
Algorithm: Algorithm is a finite sequence of well defined steps or operations for solving a problem in systematic manner.
It is also called step by step solution.
A Flowchart and an algorithm are used to preparefirst before writing program.

13. PROGRAM CONTROL Symbol Name Description Rectangular or action
A process or an action such as calculation and assignment
Oval
Begin/start or End/stop. Indicates a completed algorithm or program flow
Diamond or decision
Indicates a decision to be made such as YES/NO, TRUE/FALSE, <, <= etc.
Flow lines
Indicates the order of the actions to be executed, connecting other symbols
Small circle or connector
Indicates a portion of a complete algorithm continued from the previous portion or to be continued to the next portion
Input or output
The input or output such as standard input or output

14. Flowchart for Largest of 3 No's A,B,C

15. Algorithm for Largest of 3 No's A,B,C
Step1: Read A, B, C
Step2: If A > B is True, then check whether A > C, if yes then A is greatest otherwise C is greatest
Step3: If A > B is False, then check whether B > C, if yes then B is greatest otherwise C is greatest