Called the "king of spices", pepper has a long history of being used as a seasoning, a preservative, and even currency. By far the most frequently used spice, pepper blends and mixes add an excellent depth of flavor to nearly any savory dish, and many sweet dishes as well. Black, white, and green peppercorns all come from the same vine. They grow in clusters (like grapes), and are harvested in various stages of growth. Green peppercorns are young when they are picked and dehydrated, with a resulting mild flavor. The black peppercorns are left on the vine to fully mature and develop a stronger flavor profile. White peppercorns are actually black peppercorns, which have been soaked to remove the outer casing. This gives the white peppercorns a more intense flavor, with a slightly fermented taste and smell from the soaking process. Peppercorns begin to lose flavor as soon as they're ground, so for peak flavor, grind pepper as you need it. The Spice House grinds Tellicherry black pepper and Malaysian white pepper in small batches for great fresh-ground flavor. Ground Tellicherry pepper is available in a range of particle sizes from cracked to powdered.
See a video of The Spice Boss explaining everything you need to know about peppers.