void - No Type

void means "no type" in three contexts.

1. No return value

c
void greet() {
    printf("Hi!");
}

2. No parameters

c
int main(void) { ... }

3. Generic pointer

c
void *ptr;

A void pointer can point to anything; cast to a real type before using.

Example

c
void *data = malloc(100);
int *numbers = (int *)data;

TL;DR

• "No value".
• void return: nothing returned.
• void parameter: takes nothing.
• void *: generic pointer, cast to use.