A hot air balloon is a cloth bag, open at the bottom, with a large basket carrying the passenger and a heater suspended just below the bag opening. The heater warms the air inside the balloon, making it lighter than the surrounding atmosphere, and causing the balloon and its cargo to rise.

Modern hot air balloons are usually made of synthetic fabrics in order to reduce weight. The heater is a flame-thrower type furnace fuelled by propane gas stored in pressurized bottles. The direction of flight depends on the wind, but the altitude of the balloon can be controlled either by changing the temperature of the heater or, if passengers need the balloon to rise rapidly, by throwing ballast out of the balloon.

The lift of the balloon is determined by the temperature difference between the inside and outside air. 

One attractive aspect of a hot air balloon ride is the exceptional calmness and the birds-eye views. Since the balloon moves with the wind, the passengers feel absolutely no wind during the flight.

The dangerous aspects of the sport include excessive (vertical or horizontal) speed during landing, entangling high voltage power lines and in rare occasions, mid-air collisions that may collapse the balloon.