INTRODUCTION TO C PROGRAMMING

In ever changing world  of computing every now and then programming languages are invented and forgotten but C as a programming language has proved be the foundation for future languages.

In my earlier days when i started learning c programming it felt as if  it  is a very difficult language to understand but eventually it turned out to be  a very interesting and exciting piece of code.more-soever i would like to welcome all of you who are interested in learning c programming. Many would think that why should we learn c programming nowadays when there are programming languages more advanced than C but i believe that in order to understand all the modern languages we must understand C as a language because all the new languages have inherited much of there features  from C programming.

In order to master  any programming language one has to understand one simple concept

ALL PROGRAMMING LANGUAGES ARE MADE OF STATEMENTS THAT CONTAINS SERIES OF INSTRUCTION THAT COMPUTER FOLLOWS

now that you all understand the secret behind learning not only C but any programming language i believe that we are ready to take on a exciting journey where you would find that learning C language is a lot of fun and it allows to be more in control of  your computer then you were ever before.

NOTE: FEEL FREE TO VISIT MY C PROGRAMMING PROJECT SECTION WHERE YOU WILL FIND SOME EXCITING C CODE WHICH WILL HELP YOU UNDERSTAND THE USE OF C FROM PRACTICAL POINT OF VIEW CLICK ON THE LINK BELOW TO GO TO PROJECT SECTION

PROJECTS SECTION

C PROGRAMMING BASICS

First of all the most important thing in c programming is the ability of the language itself  to allow you to get closer to the system architecture unlike many other programming languages which hide the details from the programmer.

Before we begin to write programs in C we have to understand the basic nature of C program

#include<stdio.h>   //   -------------  1

int main()  // ----------------- 2

    {        // ---------------3

          printf("Hello World");   //---------------4

          

          getchar();        //----------------5

          return 0;       //--------------6

    } //----------------7

The above program might look a bit frightening at first but in order to understand any program we have to realize that no matter how much complex a program is we have divide it in one statement at a time and finally once we understand all the statements we will be able to get the complete picture.

1. First line in our program is which is the include statement to be more precise in programming terms we call it PRE PROCESSOR DIRECTIVE now why do we need this statement or rather what we happen if we delete this statement are we going to run our program well i will answer that question and the answer is NO because this statement which happens to be the first statement in our program inform the the compiler abut certain keywords that we are going to use in our program.I know it might seem confusing because you have no idea what a compiler is or what are the keyboards but don't worry i will get to that once we finish dissecting this first c program. in short what you need to understand is that this first line does the work of a friend who knows address of some place where we want to go.. for example if we want to go to a particular place we need to have this friend with us then only we can reach our destination.

      2.The second line on our code is the main function which is the starting point of any c program and word before the main function is the return type of function well at present you won;t understand what does i means to return a value but don't worry when we go over the functions chapter i will clarify what a return value is but for the time being what it means is that every function has some purpose why it is created and return a value means returning the end result when we finish running the function.

     3. The third line which is the opening brace is the starting of a body of the c program

     4. The fourth line is the printf function from the standard c library which allows us to write on the screen

     5  The fifth line is the getchar function which allows us to enter a single character from the keyboard.

     6. The sixth line is the return value of the function , remember it is the same return value that we were talking about when we discussed about main function in the second line and again i will elaborate more on the return value when we talk about functions so if at present you are not able to get what is a return value don't panic.

    7. The seventh line is the end of the program which is indicated by the closing braces.

 

               

DATA TYPES IN C

C as a programming  language is very rich in terms of date types.Now you might be wondering what is a data type? in simple terms what it means is what type of data can be store in a variable(A variable is a placeholder for data)every variable has a type and it determines what can be stored in that variable.

Different types of data types:

INTEGER - Integer data type is used to hold a whole number(A number without a fractional part eg 2,5).
integer data type is denote by INT KEYWORD


CHARACTER - Character data type is used to hold a single character(eg. 3,m,-).


FLOAT - Float data type is used to hold a fractional number(A number with a decimal part eg 2.25,63.25).

DOUBLE - Double data type is also used to hold a fractional number but it has a greater precision as compared to float(Now might be wondering what is a precision in simple terms what it means how many numbers after the decimal point can be displayed with greater accuracy).

VARIABLES

Variables is a very important concept in any programming language because variable allow us to store information while the program is being executed and allows us to follow different course of action based upon the value stored in the variable.

DATA TYPE MODIFIERS

Date type modifiers allow us the change the context in which we use variable

Different types of data modifiers

SHORT - when variable type is preceded with the short modifier all it means that it reduces the amount of data that can be stored in a variable. Now you all might be thinking why do we need to attach short modifier
well when we declare any variable it is a place holder and depending upon the type of variable it has the some definite space allocated in the computer memory , preceding the variable name with short modifier we can reduce the the amount of space as a result we can reduce the amount  of data that we can store in the variable,well you might think why do we need to restrict ourself by reducing the amount of data that we can store in the variable , one reason for doing this is for effeciency (for example. if you have created a variable to store age of a person in that case if we declare a variable as integer it can hold approx 4 billion possible number , considering an int to be 32 bit.well we don;t need that much bigger space just to store a age of a person)

LONG -when the variable type is preceded with the long modifier all it means is that it increase the space available to store data in a variable.


SIGNED - signed modifier indicates that a variable can hold both positive as well as negative numbers

UNSIGNED - unsigned modifiers indicates that a variable can hold only positive values