A **boolean** is a data type in the C Standard Library which can store `true` or `false`. Every non-zero value corresponds to `true` while `0` corresponds to `false`.

The boolean works as it does in C++. However, if you don't *include the header file*​ `stdbool.h`, the program will not compile.

Another option is to define our own data type using `typedef`, which takes the values `true` and `false`:

```C
typedef enum {false, true} bool;
```
However, it is safer to rely on the standard boolean in `stdbool.h`.
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# Examples

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## 1. Using the header file `stdbool.h`

#include <stdio.h>
#include <stdbool.h>

int main() {
  bool x = false;
  if(x){
    printf("x is true.");
  }
  else{
    printf("x is false.");
  }
}

#include <stdio.h>

typedef enum {false, true} bool;

int main() {
  bool x = false;
  if(x){
    printf("x is true.");
  }
  else{
    printf("x is false.");
  }
}

What is boolean in C?

A boolean is a data type in the C Standard Library which can store true or false. Every non-zero value corresponds to true while 0 corresponds to false. The boolean works as it does in C++. However, if you don t include the header file​ stdbool.h, the program will not compile. 

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What is boolean in C?

Examples

1. Using the header file stdbool.h

2. Using typedef

1. Using the header file `stdbool.h`

2. Using `typedef`