Netherrack

Netherrack (previously known as Netherstone or sometimes Hellstone, Bloodstone, or Red Mossy Cobblestone), is a block that is found only in the The Nether. The dark red texture of the stone, along with its abundance in The Nether, give it a very chilling ambiance and make the region seem darker than it is. Netherrack is rather fragile and can be mined with one hit, even using a stone pickaxe. It can also be broken relatively easily by hand; however, using your hand or a tool other than a pick will drop no material. Netherrack has an extremely low resistance to TNT and can be destroyed by the Ghast's fireballs. The redness on Netherrack is moss, not blood, although some still call it Bloodstone because the name fits well for The Nether.

Once Netherrack is lit on Fire using Flint and Steel or a Ghast's fireball, it will continue to burn until it is put out by the player. This makes Netherrack a good source of light and allows the creation of Netherrack traps, such as firewalls. Fire from the burning Netherrack will spread to nearby flammable blocks, but not to another Netherrack block.

Netherrack Traps
It is possible to place several single tiles of Netherrack across one's outside home area and light them on fire using flint and steel. Animals will carelessly jump on top of the blocks, catching on fire and more often than not they will jump off of the burning Netherrack and drop loot in a safe location. After a while, many animals will kill themselves on the traps and their loot can be collected for free. Be sure not to place them near trees or wood.

Another type of trap can be made using Netherrack and Cacti. This can be done by digging a line around a chosen area and every other one place sand for the Cactus to be grown on, then lighting the Netherrack on fire.

This trap is good for placing in an open area as a per-perimeter for stopping Mobs. This works excellent against spider mobs. Spiders can jump two blocks high and can jump over fire. The Cacti will stop them from being able to get through.

Trivia

 * Netherrack, although stone, can be destroyed by hand in seconds, making it the first of its kind in Minecraft.
 * Netherrack does not emit light, however it does melt snow blocks next to it, and snow will not form on it.
 * Due to a bug, plants that normally require dirt or sand to grow on, can be planted on Netherrack when it is on fire. However, plants that grow will only increase one block in height, then disintegrate.
 * The name "Netherrack" is not a misspelling of "Netherrock".
 * It could also possibly be based on one or more of several definitions of rack having to do with suffering.

Netherstone