Torches are the original sources of light, that spread light outwards 9 blocks in a decreasing manner. Lava, Jack-o-Lanterns, and Glowstone Blocks, are the other blocks that produce light. A torch has a luminescence of 14. Daylight has a luminescence of 16. Torches are commonly used to light mines and dungeons. This makes it where mobs will not spawn which can be annoying if the player is trying to do something. Torches are decoration blocks and are the most commonly used source of light (other than natural sunlight). They are also used to light up homes. Notch has announced that in a future update, it will be necessary to relight torches with Flint and Steel. Torches can not be placed on blocks with opacity. Blocks with Opacity cannot have all standard blocks placed on them. Blocks with Opacity are as follows: Water (Source), Lava (Source), Tall Grass, Oak Sapling, Birch Sapling, Spruce Sapling, Jungle Sapling, Red Mushroom, Brown Mushroom, Red Flower, Dandelion, Crops, Sugar Cane, Cactus, End Portal, Portal, Fire, Sign, Torch, Snow, Air, Enchantment Table, Redstone Torch, Redstone Wire, Button, Pressure Plate, Lever, Rail, Trapdoor, Redstone Repeater, Door, Iron Door, Bed, Cake, Fence]], Ladder, Oak Wood Stairs, Spruce Wood Stairs, Jungle Wood Stairs, Birch Wood Stairs, Cobblestone Stairs, Bricks Stairs, Stone Brick Stairs, Nether Brick Stairs, Sandstone Stairs, Quartz Stairs, Stone Slab, Sandstone Slab, Cobblestone Slab, Bricks Slab, Stone Brick Slab, Oak Wood Slab, Jungle Wood Slab, Birch Wood Slab, Spruce Wood Slab, Nether Brick Slab, Quartz Slab, Farmland, Chest, Large Chest, Glowstone, Piston, Sticky Piston, Oak Leaves, Jungle Leaves, Spruce Leaves, Birch Leaves, Glass, and Ice.