laravel updateOrCreate

// If there's a flight from Oakland to San Diego, set the price to $99.
// If no matching model exists, create one.
$flight = App\Flight::updateOrCreate(
    ['departure' => 'Oakland', 'destination' => 'San Diego'],
    ['price' => 99, 'discounted' => 1]
);

$user = User::updateOrCreate(
    ['email' =>  request('email')],
    ['name' => request('name')]
);

// Do other things with the User

// If there's a flight from Oakland to San Diego, set the price to $99.
// If no matching model exists, create one.
$flight = App\Models\Flight::updateOrCreate(
    ['departure' => 'Oakland', 'destination' => 'San Diego'],
    ['price' => 99, 'discounted' => 1]
);

$userData = array('username' => 'Me', 'email' => '[email protected]');
User::create($userData);

firstOrCreate() will automatically create a new entry in the database if there is not match found. Otherwise it will give you the matched item.
firstOrNew() will give you a new model instance to work with if not match was found, but will only be saved to the database when you explicitly do so (calling save() on the model). Otherwise it will give you the matched item.