equivalence/if and only if

The opposite of an XOR, if something is T and T, then it would be T when applied.

• http://mathworld.wolfram.com/XNOR.html

Definition (in your own words) of the chosen keyword.

List any sites, books, or sources utilized when researching information on this topic. (Remove any filler text).

• Reference 1
• Reference 2
• Reference 3

Demonstration of the indicated keyword.

If you wish to aid your definition with a code sample, you can do so by using a wiki code block, an example follows:

/*
 * Sample code block
 */
#include <stdio.h>
 
int main()
{
    return(0);
}

Alternatively (or additionally), if you want to demonstrate something on the command-line, you can do so as follows:

lab46:~$ cd src
lab46:~/src$ gcc -o hello hello.c
lab46:~/src$ ./hello
Hello, World!
lab46:~/src$