Void function return value is used

Void functions are functions that do not return any value. It means that they are meant to be used to perform certain actions or operations, but not to return any value. However, if you try to use the return value of a void function, you will get a warning or error message that says "Void function return value is used".

For example, consider the following code:

function printMessage(message) {
  console.log(message);
}

let result = printMessage("Hello, world!");

console.log(result);

In this code, the `printMessage` function is a void function that simply logs a message to the console. However, we are trying to assign the return value of this function to the `result` variable. Since the `printMessage` function does not return any value, the `result` variable will be `undefined`.

To avoid this warning or error message, you should not try to use the return value of a void function. Instead, you should simply call the function to perform the desired action or operation.