Stairs

Stairs are blocks that allow the player to change elevation without jumping. They are a more compact alternative to Slabs, allowing a greater elevation change in a shorter horizontal distance.

Crafting
Stairs can be made from six wooden planks or six cobblestone, producing four stairs per craft. Upon destroying the block after placement, it will yield only one of the original material.

Behavior
As of version 1.2.0 (the Halloween update) Stairs are placed facing the player so they may be immediately climbed. This may cause problems when constructing a stair; just start at the lower end to fix this. Alternatively, you can face the top of the stairs, sneak, and place stairs at your feet while hanging onto the edge of a block to place them in the correct location while descending the stairs.

Water will flow over stairs as if it were a completely solid block. If one attempts to place a torch on top of a stair block, the torch will be placed instead on the closest available non-stair block.

As of Alpha version 1.2.0_02, stairs have the odd property of being transparent to light; when placed one or more spaces above the ground with air beneath, sunlight or other light sources will shine through and light the blocks beneath/behind the stairs exactly as if nothing opaque were present between them. Other atmospheric effects such as snowfall do not penetrate stair blocks, making them an unusually effective material for creating roofing which keeps weather out, yet allows daylight in. Snow cannot accumulate on top of stair blocks. Grass can grow on the block directly underneath a stair block, and grass will not disappear if a stair block is placed on top of it. Wooden stairs will not burn.



Glitches
There is a glitch where when stairs are placed at the water's edge,(with the top edge of the block at the water's level) Any boat going at any speed can collide with it with no damage to the boat, making it ideal for the creation of a dock.

There is also a glitch where stairs appear invisible,this is caused by the game not recognizing stairs (and fences) as a block that needs to be shown in a chuck. placing a non-stair block inside the 16x16x16 chunk will cause the stairs to appear.(source)

Another glitch is where chests under stairs can be opened.





History

 * At some viewing angles, hovering the cursor over the stair block would make the black outline flicker, making mining the stair block glitchy, and the block behind it would often be mined instead.


 * Stairs used to face a direction automatically when placed. They would attempt to face a block adjacent to the stairs, so as to create a climbable surface towards that block. However, this was often more annoying than helpful, and was therefore changed to be placed facing the player.