Piston

Pistons and Sticky Pistons are both Redstone-related blocks capable of pushing other blocks when given a power source. They should be added in Update 0.15.0.

Crafting

 * 3 Wooden Planks + 4 Cobblestone + 1 Iron Ingot + 1 Redstone => 1 Piston
 * 1 Piston + 1 Slimeball => 1 Sticky Piston

Sticky Pistons
Sticky Pistons behave similar to regular pistons, however, they are also capable of pulling the object they are attached to.

Behavior
Normal pistons can move up to 12 adjacent blocks but cannot pull them back. Sticky pistons can only push and pull one block at a time.

Trivia

 * Pistons cannot push all types of blocks.
 * For example, blast resistant blocks like Obsidian or Bedrock cannot be pushed by a piston.
 * Pistons also cannot move Tile Entities like Chests and Liquids like Water and Lava.
 * They also cannot push Furnaces.
 * Pistons were originally going to be added in Update 0.14.0, but were delayed till Update 0.15.0.
 * When a Slime Block is attached to a Piston, it moves all blocks adjacent to the Slime Block.
 * Version Exclusive: Pistons have a bulked lower piston extender (lower neck of the piston)
 * When used together, Pistons, Sticky Pistons, Blocks of redstone and Slime Blocks can make very advanced redstone mechanics such as Walking Robots, Cars, Trains, Planes, Launchers, etc.