01.Computer programming

Computer programming is the process of writing instructions that get executed by computers.

There are various kinds of programming languages out there designed for various purposes.some of the popular programming languages are

c/c++
c # (known as c sharp)
Python
javascript
java
perl
swift
php
visual basic
vb.net

These programming languages can be cassified into 2 major categories.

1.Procedural programming-The procedural programming language is used to execute a sequence of statements which lead to a result


2.Object oriented programming-In oop,
the emphasis is on data rather than procedures,
the programs are divided into objects

The c++ is an example of object oriented programming.

The oop includes classes and objects,
e.g consider following part from a c++ program

int main()
{
shape circle;
circle.getdata();
circle.calculate();
return 0;
}


then the shape is class and the circle is an object under class shape.


for a clearcut explanation, watch this video

https://www.youtube.com/watch?v=70sld4fYcqU

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Programming in c++ 

In linux you dont need to download any compiler.
Just right click on desktop and create an empty file and start programming. after programming, save the file with .cc extension.

1.Downloading c++ compiler (for Windows)

In order to compile a c++ program, you need to have a compiler..there are various c++ compilers out there.
.
code::blocks is one of those..

you can download that for free from following link.

Download code:block

after downloading code::blocks , install this program.

2.Making 1st c++ program- Hello world

now we are ready to see , how a c++ program is built and run.

• open code::blocks 
• go to file->new->empty file
• type the following code in the compiler

#include<iostream>

using namespace std;

int main ()

{ cout<<"Hello World!";

return 0;

}

save the file with .cpp extension
press f9 to execute  the program



3.Understanding the program

1.#include<iostream>

This statements tells the compiler to include iostream file. This file contains pre defined input/output functions that we can use in our program.

2.Using namespace std; 

We use the namespace std to make it easier to reference operations included in that namespace.
without using namespace, we would have to write std::cout instead of cout. This tells the compiler that every cout is actually std::cout.

3.int main ()

This is the function from which the compiler starts executing program

4.cout <<"hello world!";

cout means console out . it is the standard command used to display output.

<< is the insertion operator.

5.return 0;

This command tells system “The program worked fine.”


in the next post, you will get to learn about making some simple programs