Although a paraglider lacks an engine, it flies by utilizing aerodynamic principles. Just like a glider, its wing shape creates a pressure difference between the upper surface (extrados) and the lower surface (intrados). This pressure difference generates an upward force called lift, which counteracts the force of gravity and allows the paraglider to stay in the air. To generate lift, the paraglider must move forward. For this reason, takeoff always occurs from a high point, such as a mountain, which allows the aircraft to gain the necessary speed. In the absence of mountainous terrain, as in Northern Europe, a tow by an airplane or a winch is used to give the paraglider the initial speed. But how does a paraglider climb without an engine? The key is ascending air. Imagine blowing over a sheet of paper: the sheet rises. The same principle applies to the paraglider. When the paraglider encounters an updraft that rises faster than the aircraft descends, it is literally lifted upwards. These updrafts, called thermals, form due to the heating of the ground by the sun. Experienced paraglider pilots learn to recognize and utilize thermals to gain altitude and prolong their flight.