Sign

Signs are blocks that have text on one side of them. Signs may be used to mark property, leave directions, state rules, or even leave out your poetic stylings for travelers to stumble upon. Signs can also be used to create furniture such as the sides of chairs or ends of beds.

Signs are one of the many blocks that are broken more quickly with a sword, but still deal double damage to the sword. The breaking animation also doesn't play.

History
Signs were originally added in Survival Mode, but removed shortly after. They were re-introduced in infdev, where they would have greater use. As of the 07/02/10 update (Seecret Friday update #3) signs became smaller.

As a block
Signs count as a regular block, except mobs and items can pass through them. This means that other blocks can be placed on top of a sign, and wall-clinging blocks can also be placed on their sides.

Water cannot enter the space occupied by a sign, so signs, like ladders, may be used to make a doorway through which water cannot flow.

Writing
After placing a sign, a window pops up where the player inputs the text that will be placed upon the sign. Four lines of text are available, with 15 characters on each line. The sign's text may only be changed by removing it (which will discard the text) and placing it again. To write switch lines, the player can press Enter or the up/down arrow keys. Once a line has 15 characters, no more text can be inputted on it. In SSP, the game pauses until the player finishes typing.

Placing
One can place signs in the ground sticking out, or on walls without any post grounding them. Signs may be placed attached to any block, including ones such as fences, glass, other signs, and minecart tracks, which torches cannot be attached to all except to fences in 1.7.2 and above.

Free-standing signs can face one of 16 directions, and face toward the player when placed. Wall-mounted signs can only face the four cardinal directions, and are attached to the face the player clicks on of an existing block.

Due to the South/West rule, signs can be used to create a Water Ladder, which allows the player to ascend quicker. However, a door may be more efficient for entrances to the ladder from the ground, as doors only need the 6 wooden planks, and not the stick.

If a sign is placed underwater, either on the side of a block or on top of another sign, an air bubble will form, allowing the player to breathe underwater.

Colored text
Text in signs can be colored. The section sign (§), followed by a number from 0-9 or a letter from A-F, will change the color of the following text on the current line. Unfortunately, one cannot enter that character normally in the game, so one must use a map editor to do so. The section sign and the following hexadecimal number also count towards the 15 character limit.

Bugs

 * In SMP, if a player destroys a placed sign while another player is writing on it, the text prompt will not disappear.
 * Like Paintings, Signs do not use the Smooth Lighting function when enabled.
 * If you put all fifteen characters as tildes (~), the first and last two tildes are in mid-air instead of on the sign.
 * Also, if you put fifteen @ characters - the same thing happens
 * If a sign is placed during the portal animation, "w" will be on the first line of text, and no text can be entered.
 * When a sign is placed on a gravity affected block that was generated floating, the block will fall and the sign will be lost.

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