Item Frame

The Item Frame is an item similar to a display case. It displays the item or block that is inside it. Players can place items in the frame by right-clicking while holding the item. The displayed item can be rotated by right-clicking the frame. Maps show their contents, and compasses and clocks work as normal. When broken, the frame drops both itself and the item it contains. Because item frames are technically entities like paintings, they can be broken in Adventure Mode.

Uses
Item frames have many uses, and can be placed on cactus blocks, fences, slabs and cobblestone walls, along with all solid blocks. The player can place items into item frames by right-clicking with the held item in hand.

The player can use item frames to hold items for convenient retrieval or reference, instead of having to open a chest or dispenser to retrieve or verify specific items. This means item frames can be used to label chests, dispensers, etc. This also allows working clocks and compasses, as well as maps, to be displayed against a wall. A map put into an item frame will show markers at any other item frames with maps in them. This is a good way to mark certain areas.

Items frames can be used to display crafting and brewing recipes, and can also be used to hold fire, allowing for safer fireplaces.

Since items in the frame can be rotated, this allows for directional pointing using items that are shaped like pointers or wedges - such as arrows, tripwire hooks, flower pots, redstone, etc.

Since levers, torches, and buttons can be placed against the item frame, this allows for color-coded levers (using colored wool), decorative torch holders (using slabs or trapdoors), and decorative gold trims for buttons (using an item frame inside the item frame). Item frames can be used similarly as signs, allowing for decorative armrests for chairs.

Item frames can be placed against piston heads to make better-looking frames.

In Creative mode, items can be cloned by placing multiple copies of the same item in different frames. This is a handy way to clone enchanted weaponry or tools although items can only be retrieved in Survival mode. It is also possible in Creative mode to place multiple item frames on the same block after restarting the save. This allows the player to stack items in the "same" frame by placing an item in the frame, saving/quitting to the main menu, and restarting the save. After restarting, it is possible to place another item frame on the same block as the existing one, and the player can then place another item in the new item frame (the first item cannot be rotated after restarting the save). This can be repeated multiple times unless the entity limit is reached.

Bugs

 * The Pick-Block key gives the item in the frame, as opposed to the frame itself (may be intentional).
 * Torches can be placed on item frames, but only indirectly (possible feature)
 * If the block an item frame is placed on is moved by a piston, the frame will not move. However, the frame will break upon walking into it.
 * When placing an enchanted item in the frame it appears unenchanted.
 * If you put more then one item (in a stack) in it and mine the frame you will get only one of the item back.
 * If you have an item frame on your field of view, mobs will sink through wooden planks (but not wooden slabs).
 * When more than one item frame is filled with the same map, only the first map is marked on by a green marker, as opposed to both of them (may be intentional)

Trivia

 * The item frame is based off a suggestion on Reddit, like the Ender chest and flower pot.
 * Item frames can occupy the same block as water without popping off.
 * Items appear flat in the frame while blocks protrude from it.