Skydiving orParachuting is a sport in which you exit a plane from altitude, freefall for a while and then deploy a parachute to fly safely to the ground. This page doesn't describe activities such as parascending down a mountainside or on tow behind a motorboat, where you have an open parachute right from the start; nor the hazardous sport of BASE jumping (e.g. from buildings and bridges).

Skydiving doesn't work as a spectator sport because the action is too far from the ground. Sometimes teams parachute into an event, but it's just a curtain raiser to a ball game or an interlude at the county fair between the pipe band and the police dog display. Many skydivers wear cameras and download their footage back on the ground, but there isn't yet the technology to transmit images in real time. And screen images hardly convey the blast of plunging out of an aircraft into a roaring slipstream. So if you want to experience it, you have to buckle on a kit and get in that plane.

There are three main ways to get started.

• Tandem is where you jump buckled to an instructor, who does all the work. The pair of you freefall for about a minute, perhaps also with an in-air cameraman to record your horrified expression, then spend a couple of minutes under parachute. So it's more like a white-knuckle fairground ride than a sport, with minimum fitness and training needed. This is the commonest way to get started; many people only ever do one jump, as a charity challenge or bucket-list experience.

• Accelerated Freefall (AFF) is usually a follow-on from an initial tandem, but you can start straight in. You freefall independently from high altitude from your very first jump. An instructor jumps with you, giving signals to correct your body position, to check your awareness of your height, and eventually to cue your parachute opening. (The wind is too loud to talk in freefall, so you need to watch and act upon those signals.) Early jumps are just about maintaining basic stability, then you learn turns and other manoeuvres. It's an intense, immersive approach that's not for everyone, and it's more expensive; but you're a true skydiver right from the get-go.

• Static line is the old-school method; it's no longer the standard training approach but is still widely available. You're clipped to the plane by a stout lanyard, the "static-line" or "dope-rope". You exit the plane at intermediate altitude, say 4000 feet; the line almost immediately rips your parachute out to deploy then a break-tie snaps and away you float under canopy. There's no freefall so you're not yet a skydiver, but you're certainly a parachutist as you steer and land yourself. This method is relatively inexpensive and you will learn good canopy control, in-air awareness, parachute packing and other excellent stuff before progressing to freefall. You then jump freefall from higher and higher, until you come on a par with the AFF trainees.

Kit is expensive. For early jumps you hire the centre's kit, then seek advice from the instructors on what sort of kit you should look to buy, given your body size and how rapidly you're progressing. A modern parachute is a "ram air", with multiple cells that are open at the front so they inflate into a square, corrugated canopy. Your early chute will be large and docile. You'll graduate onto smaller, faster, dynamic canopies, but not too soon, as these are dangerous if mishandled. You always have a reserve, stowed on top of the main canopy in the same container. Plus it's virtually mandatory nowadays to have an AAD - automatic activation device - which is your last chance if you brain-lock and fail to open. Add helmet, altimeter, goggles, and a few other bits and bobs, and you're good to go.

Jump at an approved centre, affiliated to the relevant national governing body. These bodies hold the definitive list of approved centres for their country, and enforce standards around planes, pilots, instructors, training methods and parachuting procedures, kit packing and maintenance, and airfield facilities and location (eg not next to a fast busy highway or heavy industry). They also set out key regulations eg the minimum age for training or your maximum weight, and whether you need a medical certificate - these rules vary country by country. Below are listed some national agencies. In countries with only one or two centres, realistically there may not be a national body, and the centres set their own rules or affiliate to an outside agency such as the US. Check whether yourhealth insurance covers this activity: it probably will for your home country, but travel insurance will need a supplement.

Next steps: after falling for 13 seconds, you're going as fast as you will, a terminal velocity of 120 mph / 190 k/hr in a "flat-fly" or belly-to-earth position. It doesn't feel like falling, because you're always flying in the onrush of air, as if balancing atop a fountain. Use small movements of your body to turn, shift forward or back, fall slower or faster and so on, in a controlled manner. From there you learn to link with others in "formation skydiving" - and to separate safely before it's time to open. Four is the basic formation team, then eight, and bigger. "Freestyle" means falling in other positions such as head-down, which are much faster and dynamically unstable. Other disciplines include wing-suiting, gradient flying, parachute landing accuracy, surfing ie steering your canopy through a slalom course, and CRW where open canopies are linked. You'll also start to train others, and might work to become an instructor or parachute rigger. All this involves a major commitment of time and money.

How high you go varies between centres, but 15,000 feet above sea level is the standard ceiling. That's because you climb rapidly from near sea level in an unpressurised aircraft without acclimatisation, so you can't safely go higher without oxygen. That height allows you 70 secs of freefall before opening at 3000-4000 feet. However some radical folk go lower: they use wind tunnels as training grounds. These have developed to the stage where four-way wind tunnel competitions are held, but they've not yet become a free-standing sport or alternate training pathway into skydiving.

You can skydive in just about any country with well-developed civil aviation and a population base to sustain the sport. Some national agencies are listed below, otherwise, just try an online search, thus "Skydiving in Bulgaria" nets you four possibilities. The bigger centres are open all year, but they have to work around the weather, and the off-season involves a lot of gloomy folk staring at gloomy clouds wondering if they'll manage a jump today. You'll probably need your own wheels, as these airfields tend to be way out in the country with scant public transport. That's so they won't have to share their airspace with airliners and business jets flying on instruments, as bodies hurtling in freefall are notoriously deaf to Air Traffic Control.