Kingwood Computer Programming

Learn to Code

Why Learn C?

► Many of the most popular current programming languages share significant syntax with C.

Here's a program in C to sum the numbers from 1 to N (file: test.c):

#include <stdio.h>

int getSum(int value)
{
   int sum = 0;
   int i   = 1;

   while(i <= value)
   {
      sum += i;
      i++;
   }

   return(sum);
}

int main()
{
   printf("%d\n", getSum(20));
   return(0);
}

And here is the corresponding code in java (file: test.java):

public class test
{
   static int getSum(int value)
   {
      int sum = 0;
      int i   = 1;

      while(i <= value)
      {
         sum += i;
         i++;
      }

      return(sum);
   }

   public static void main(String[] args)
   {
      System.out.printf("%d\n", getSum(20));
   }
}

In C++ (file: test.cpp):

#include <iostream>

int getSum(int value)
{
   int sum = 0;
   int i   = 1;

   while(i <= value)
   {
      sum += i;
      i++;
   }

   return(sum);
}

int main()
{
   std::cout << getSum(20) << "\n";
   return(0);
}

In C# (file: test.cs):

using System;

public class test
{
   public static int getSum(int value)
   {
      int sum = 0;
      int i   = 1;

      while(i <= value)
      {
         sum += i;
         i++;
      }

      return(sum);
   }

   public static void Main()
   {
      Console.WriteLine(getSum(20));
   }
}

In PHP (file: test.php):

<?
   function getSum($value)
   {
      $sum = 0;
      $i   = 1;

      while($i <= $value)
      {
         $sum += $i;
         $i++;
      }

      return($sum);
   }

   printf("%d\n", getSum(20));
?>

And finally, javascript (file: test.js):

function getSum(value)
{
   var sum = 0;
   var i   = 0;

   while(i <= value)
   {
      sum += i;
      i++;
   }

   return(sum);
}

alert(getSum(20));

Clearly there is some merit to the claim that many other popular languages have significant syntactical overlap with C!

Source Code

► Further, while languages like c++, java, c#, php and javascript are constantly changing and evolving, c has remained more steady. Standards-complaint c programs written decades ago still compile and run without any problems.

► Additionally, C is just a more straightforward language than many other popular languages like: c++, java, php and c#. The C89 standard lists a total of 32 C language keywords, here are the totals for several languages:

Language	Number Of Keywords
C (1989)	32
C (1999)	37
Java	52
PHP	70
C#	77
C++	97

As you can see, the other languages have two or even three times as many reserved words as C does.

► Many programs that are used all over the world every day are written in C:

Program Name	Description
Linux	Operating System
GIT	Version Control
Apache	Web Server
Python	Programming Language
PHP	Programming Language
Perl	Programming Language

► As of July, 2021, the TIOBE Index of programming popularity was:

C
Java
Python
C++
C#

So, (the merits of the TIOBE index notwithstanding) it's pretty clear that even though C is much older than the other languages it is still quite popular.

► ONLINE RESOURCES

► COMPILERS

► TEXTBOOKS

C Programming - A Modern Approach (highly recommended but expensive, $90+)
The C Programming Language, 2nd Edition (more reasonable, about $35, old school)
The C Book (free online)
Modern C - Jens Gustedt (free online)
C: A Reference Manual, 5th Edition

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