The US also has a light sport aircraft (LSA) category and a sport pilot license with less requirements but more restrictions. While the 40 hours is a minimum,

The US also has a light sport aircraft (LSA) category and a sport pilot license with less requirements but more restrictions. While the 40 hours is a minimum, most people require more to complete their PPL training and pass their exam. Some aircraft do not require a pilot license but I’m hard pressed for good reasons to fly without prior training.