% things please elaborate

Alright I am reading my book and I am going along fairly well untill I came to something like this

printf("%c", ctr")

now I know what printf is, and ctr is the variable that I had to make before the confusing part is the %c thingy.
I am not sure but I think that it does something special(this program displays all of the letters of the alphabet, woo big thing here, lol)anyways if I am right(which I probably am not)does anyone have an explanation or a list that I could have that lists the different ones and their uses if you don't mind.
Please and thanks in advance.

%c signifies that your variable is character specific. It will be a character.

printf("%s", "Hello World")
The string, is Hello World.

printf("%s", HelloWorld)
The string is a string of text stored in the variable HelloWorld.

The %c is a place holder, and tells printf to read the next argument into that place and print it. It performs this function in order. There are a number of place holders for different data types.
%s for strings
%i for ints
So something like the following should work

Code:

int main()
{
char []mystring={"Hello"};
int myint=15;
printf ("My string is %s, but my int is %i",mystring,myint);
return 0;
}

The arguments are taken in order, and your compiler should generate an error or warning if you try to pass a string to a %i placeholder say.

You can also expand upon these place holders with formatting information. Look here for more info;
http://www.cplusplus.com/ref/cstdio/printf.html

OK so if I can "call" an interger or character by using those symbols like:

int mine=10
printf("%i, My interger is:, mine")

would something along this line(not exactly this line)would work though??

Not quite.

The variable you pass needs to be outside the quote marks

printf("My interger is: %i", mine)

would more likely give the result you're looking for.

Alright so if I am doing something like you example what is the point, like why not just type it(unless this acts like a variable)and how does the compiler or whatever know which intergers are which and which ones to place with %s??

I'm not sure of your question but heres a bigger example, hope this helps:

Code:

int main()
{
  int money=5;
  char name[5];
  int average=15;

  strcpy(name,"me");
  printf("My name is %s I have %d dollars and average of %d",name,money,average);
  return 0;
}

ok now %d means an integer, %s means a string, the compiler will go through and see that the first variable that is out of the "" part will be a string followed by an integer, followed by another integer, etc. so whatever the order is in your string to print to the screen must be the same as what you put in the printf statement.

Here is a small program displaying what's been discussed:

Code:

#include <stdio.h>

int Again ( char * NewLine );

int main ( void )
{
	#define MESSAGE(x) printf("This is line 1\n%s\nThis is line 3\n\n", x);
	MESSAGE("This is a new line");
	MESSAGE("This is another new line");
	Again("This is a new line again");
	Again("This is another new line again");
	return 0;
}

int Again ( char * NewLine )
{
	printf("This is line 1\n%s\nThis is line 3\n\n", NewLine);
	return 0;
}

A variable, is sort of like a wildcard. It's sort of like a joker in a deck of playing cards.

In the function Again(), NewLine is the variable. %s in the printf statement says that it will be a string. The NewLine variable at the end of the printf statement, is the "container" which holds your string of text. This can be changed. In the function title or definition of Again, you see the variable NewLine. Well, when we call Again in the main program, we can always change what would normally be line 2. In the main function there is another example by using a define statement.

Alright I will keep trying so thanks.