Vines

Vines (sometimes called Ivy) were included in the Adventure Update and are placeable on walls and ceilings.

Vines have the same color of the foliage in a specific biome. They also hang on leaves in Swamps.

Vines are a non-solid block but have a collision box, so the Player can stand on them and can walk through them like ladders.

Vines take as long to break as leaves and drop nothing if broken with hands. However, they can be collected using shears. Although they can be placed after collection, they can only be placed on a solid block, not in the air. Breaking the block after vines are placed on it will also break the vines.

Vines are most effectively destroyed by water; vines on a tall structure, for example, can be easily flushed away by placing a water source block at the top of the structure. Vines are much easier to obtain than ladders (if near swamp and jungle biomes), and therefore, are particularly useful if the player runs out of ladders, does not want to use ladders, or does not have any ladders at hand. Vines cannot be placed directly on blocks like chests, Crafting Tables and Cobwebs; however, they can be grown around them. The player cannot place vines under another vine where there is no blocks (like how vines hang off the trees that are naturally generated). To do so, the player will need to put a block under the block of the original vine, place the vines on that block and destroy it, the vines will then hang off the first vine. If the vine that is on the block is destroyed, each other hanging vine will be destroyed as well. Vines mostly spawn in the Jungle biome.

Uses

 * Vines greatly reduce the chances of taking fall damage in jungle biomes since they absorb all fall damage.
 * When descending vines, if the vines overhang an empty space, it is possible to continue descending from the vines as if there were a block there.
 * Vines block mobs' line of sight, so it is possible to sneak up onto mobs by hiding behind vines. Because of this, Endermen can be safely viewed through vines.
 * Similarly to Paintings, vines can be used to hide other blocks or passageways such as doors or even portals (possibly a bug) allowing the player to create hidden passageways or concealed blocks.
 * Vines can be climbed, but the Player must first push into a block then look up, similar to climbing ladders.

Farming
As of 1.2, Vines now have a use, making it profitable to farm them. Vines will grow into and open space below them. Making a bar a few feet off the ground, and then attaching a row of vines below it is the most efficient way to farm them.

History

 * Vines were introduced in Beta 1.8pre1.
 * On Sept 13, Notch said that he would change the vines to spread infinitely down, but would not grow other directions if there are more than four other vine blocks nearby.
 * At PAX, vines hadn't been given a name, and a mouseover would not show a title. This implies that they didn't have an official name at the time.
 * As of Beta 1.8.1, they take as long to break as leaves and drop nothing, but can be collected with shears.
 * In the 1.8 Pre-release if the player attempted to place Vines in the Nether, the game would crash.
 * In snapshot 12w03a, vines became climbable (provided the player climbs it against a solid block).

Bugs

 * Multiple vines can be in the same block space, but count as one block for most purposes. See Talk for discussion
 * If you keep placing vines onto the same square, it will use up your vines but only place a single one.
 * Vines seem to have a bug where they can grow behind paintings.
 * Vines will disappear if a torch is placed on them.
 * Vines can spread onto Portal blocks (possible bug or feature).
 * When set on fire, sometimes the vine block disappears and smoke appears, then other blocks around it catch fire.
 * When held and viewed through third person view or held by another player, vines have a gray texture, like Lily Pads.
 * Sheep can climb vines in multiplayer to escape things such as a pit. (Needs Confirmation)

Trivia

 * When harvesting hanging vines it is important to remember to work from the bottom upwards for maximum yield. Breaking a hanging vine will destroy all sections lower than it but will only yield one piece of vine, regardless of how many pieces were destroyed.
 * If blocks are placed near a vine (such as the case of having a house built in a swamp biome, for instance), vines will start growing on the wall.
 * Vines can grow in any direction when placed on a block. When there is no block next to the block where the vine is on it can grow to the side of the block. The vine can even grow up, But not if there are four other vine blocks nearby.
 * When vines grow down they don't need a block below them to attach to, however, the top-most vine needs a block in order to attach the entire vine.
 * You cannot place vines directly below blocks but they can grow under blocks.
 * When placed on a wall that is touching the bottom of a block, the vine will also attach to the bottom of the block.
 * Vines have the ability to support sand and gravel. However, unlike other such blocks, vines will be destroyed when sand or gravel attempts to occupy the space adjacent to the vines.
 * Sometimes when players place vines onto cobblestone, it might be mistaken for Moss Stone.
 * Vines make the same noise as grass when stepped on.
 * If a player holds the Shift key, they can cling onto hanging vines that aren't adjacent to any blocks.