In my opinion, checklists are very important because they’ll provide the necessary steps for the airplane’s correct configuration, and the pilots won’t have to rely on their memory since they can read and confirm each step and this will also contribute to a safer flight. Checklists are mandatory and we use them on every phase of the flight from engine startup to engine shutdown, especially in an abnormal or emergency situation. That’s it
Based on my knowledge, the differences are that the international flights are normally long-haul flights performed mostly by wide body airplanes, the pilots only make one leg per day, and they also need to consider the different regulations on their destination country, the pilots need a minimum level 4 on the ICAO English test, and these flights normally happen during the night. ON THE OTHER HAND, national flights happen inside the country and they are what we call domestic flights. These flights are performed by narrow body airplanes and the pilot’s normally do 5 or 6 legs per day.
They are completely different, my first aircraft was a Cessna152, which is a very basic single engine propeller airplane with capacity for 2 pilots, used mostly for flight training and recreational flights. Today I fly an Embraer 195, which is a twin-engine jet. We have capacity for around 120 people and we fly at 40,000ft, it’s a commercial aircraft used to transport passengers around Brazil and South America. My current airplane is bigger, faster and more technological than my first airplane.