What's the simplest way to learn pattern programs in C language?

Sometimes we see  that  a loop is written inside body of another loop-

for( i = 1 ; i <= n ; i++)

{

  for( j = 1 ; j <= n ; j++)

  {

     ........

     ........

  }

}

It is called nesting of loops.  Any type of loop can be nested inside any other type of loop.

  Consider a pattern -

  

  *

  * *

  * * *

For this we can write a C code as :

for( i = 1 ; i <= 3 ; i++)

{

  for( j = 1 ; j <= i ; j++)

  {

     printf("* ");

  }

  printf("\n");

}