Let’s clean some data:
$data = ['apple', '', null, 'banana', false];
$clean = array_filter($data);
// Result: ['apple', 'banana']

By default, array_filter() removes falsey values: null, false, ‘’, 0, etc.

But you can pass your own logic:
$even = array_filter([1, 2, 3, 4], fn($n) => $n % 2 === 0);
// Result: [1 => 2, 3 => 4]