An altimeter keeps track of your altitude. All types of aircraft feature altimeters. They tell you how far you are from the ground or terrain below. It helps you maintain necessary clearance as well as keeps you a safe distance away from other gliders or aircraft. Altimeters used by paragliders measure altitude based on air pressure. They are usually digital and built inside a variometer, GPS or sports watch.
Variometers (also called varios) are indispensible to paragliders. It tells you how fast you are climbing or falling, relative to the ground. They're used mostly for thermal lifting. Varios have audio indicators, so you don't have to bother looking at them. When you hit a certain vertical speed, the vario will start to beep, with the pitch increasing as your lift increases (or decreases as you sink). You can also check a digital readout to see your speed in a variety of measurements.
Paragliders use radios to keep in touch with other pilots as well as people on the ground. Paragliding instructors always use radios when they're training new pilots. Usually the microphone is right in the helmet so the pilot can stay in constant contact with his or her instructor on the ground.
Global positioning systems (GPS) are becoming quite popular with paragliders and other recreational aircraft pilots. Using a GPS, a paraglider pilot can assess his or her speed and follow preset routes. Some people also use the GPS once they've landed to analyze their routes and flying patterns to see if there's room for improvement. In competitive paragliding, a GPS is necessary to prove that a pilot hit all the required turning points in the race route.
In the next section we'll talk about how you can learn to paraglide.