$collection = collect([
['account_id' => 1, 'product' => 'Desk'],
['account_id' => 2, 'product' => 'Chair'],
]);
$collection->implode('product', ', ');
// Desk, Chair
$collection = collect([1,2,3,4]);
$collection->each(function($item){
return $item*$item;
});
// [1,4,9,16]