While some may use these terms differently, here are some common definitions:Javelin Turns
--This is an exercise in which you lift the inside ski off the snow and twist it with your leg so that the tip crosses over the tip of the other ski. I've never been a big fan of it in general, but many instructors like to use it to develop balance and to prevent "rotation" of the upper body and hips into the turn. It keeps the pelvis somewhat countered (facing toward the outside of the turn).Royal Turns
--By this, I assume you mean "Royal Christies," also spelled "Reuel Christies." This was an old freestyle move in which the skier balanced on the inside ski of the turn while lifting the outside ski up high and often tipped down so that the ski was vertical or even "base up" behind him or her.White Pass Turn
--This was a technique made famous by the Olympic, World Champion, and World Cup Champion Mahre brothers--Phil and Steve--and named after the White Pass ski area where they grew up. It was basically a turn with a very late weight transfer. The turn started on the inside ski, causing the skier to move his body way inside the turn for balance. Somewhere usually around the fall line (half way through the turn, when the skis are going straight downhill), the skier switched to balance on the outside ski. Since you can get a lot of pressure on a ski in the second half of a turn, and that outside ski was tipped to a high angle, and the skier was way inside the turn, the ski could finish the turn carving cleanly and fast. The Mahres insisted that it was never a move they "tried" to do, or did intentionally. In fact, both they and their coaches saw it originally as a technical error. But it was fast in the rare circumstances where it happened. To me, it truly exemplifies the idea that great skiing is about skills, not dogmatic techniques. The Mahres, while firmly committed to the belief that good skiing took place on the outside ski, practiced many hours and miles balancing on the outside ski, the inside ski, skiing on one ski (with the other ski waiting at the bottom), and so on, developing the skills and instincts to do whatever was needed and optimal, intuitively, in any situation.Ground Spins
--I assume that these are the 360 degree flat pivots on the snow that have been recently discussed in another thread, but I could be wrong (in what context did you come across this term?). It's a great exercise to develop balance, edge sensitivity, a feel for fore-aft "leverage," and subtle rotary skills. And it can be fun, although it can also produce some harsh falls if you catch an edge. See the thread "360 on skis"
for more discussion.Garland Turns
--Typically, a "garland" is an exercise in which the skier starts in a traverse, then releases the edges and guides the skis slightly downhill, as in starting a turn, then re-engages the uphill edges to guide and carve back up the hill, repeatedly. It leaves tracks that "scallop" up and down in a series of shallow arcs across the hill, resembling a garland draped on the branches of a Christmas tree. It's useful for practicing certain movements or sensations over and over, especially while avoiding the fear that may accompany pointing the skis directly downhill in a complete turn. It allows you to practice both the beginning and finish of the turn, while eliminating the "scary" middle part. They can be effective, but garlands have become such common and overused exercises that many Examiners just roll their eyes when they show up in an instructor exam--"how original--more garlands. . . ."