Netherrack

Netherrack (formerly known as Netherstone or sometimes Hellstone, Bloodstone, or Red Mossy Cobblestone), is a block that is found only in the Nether. 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.

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 other Netherrack blocks.

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, jumping off the burning Netherrack and dropping 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. Water will not evaporate if placed on a Netherrack block in the overworld - many think this because of the "no water in the nether because it evaporates" rule.

Another type of trap can be made using Netherrack and Cacti. This can be done by digging a line around a chosen area and placing sand in alternate blocks for Cactus to grow on, then lighting the Netherrack on fire.

This trap is good for placing in an open area as a perimeter for stopping Mobs. However, as of beta 1.2, spiders are able to climb over the wall as pictured unless an overhang is added to the top of the cacti. The damage inflicted by the wall will "reset" the spider's anger and preventing attack, unless you are not in sunlight, in which case the spider will proceed to attack you.

Trivia

 * Moving Netherrack through the use of pistons will put out any fire currently active on top of the block. However, if there are two netherrack blocks directly behind each other, the second netherrack starts burning.
 * Netherrack, although stone, could once be destroyed by hand in seconds, making it the first of its kind in Minecraft.
 * Burning netherrack can be used to keep an area clear of snow and ice more efficiently than torches due to it having a greater brightness.
 * The name "Netherrack" is not a misspelling of "Netherrock".
 * It could possibly be based on one or more of several definitions of "rack" having to do with suffering.
 * To find north, find an 'L' on the top left corner of the block. The 'L' always points north. It is also present on Cobblestone.
 * Despite being flammable, Netherrack cannot be used as fuel in a Powered Minecart or Furnace.
 * Netherrack can be mined in 50 milliseconds with a golden Pickaxe.
 * In the coding, it is referenced as "hellrock".