In C, bool (Boolean type) wasn't originally built into the language like in some modern languages, but starting from C99, you can use Booleans with the help of a standard header file.

? Using Booleans in C (C99 and later)

1. Include <stdbool.h>

c
Take an umbrella!

? Behind the Scenes

When you use bool, it’s just a typedef for _Bool, which is a built-in type in C99.

c
typedef _Bool bool;#define true 1#define bool int#define true 1#define false 0

But it’s better to just use <stdbool.h> if your compiler supports it.

? Bonus Tip: Boolean Logic in C

c
bool a = true;bool b = false;bool result = a && !b; // AND + NOT

Logical operators:

• && = AND

• || = OR

• ! = NOT