Back and neck pain often come from sitting badly for many hours.
Sit with your back straight and supported, feet flat on the floor, and your screen at eye level.
Keep your shoulders relaxed, not raised. Keep the keyboard close so your elbows stay near your body.
Stand and stretch every 30-45 minutes. A short walk resets your back.
If pain spreads down a leg, causes numbness, or follows a fall, see a doctor.