Fence

Fences are wooden wall blocks that cannot be jumped over.

Obtaining
Fences are broken most quickly with an axe.

Natural generation
Only oak fences spawn naturally:
 * Fences form the uprights for the supports in abandoned mine shafts, where they are plentiful.
 * They are also found in villages, where they appear in tables, lampposts, and even enclosures on roofs or behind buildings.
 * Fences occur in library rooms of strongholds as railings and chandeliers. In the latter case, there are many torches attached to them.
 * Fences appear on the "patios" and in the front window of witch huts.

Usage
While fences appear to be a single block tall, they are actually 1.5 blocks tall, meaning most mobs cannot jump over them. They can also be used as a form of window, since the player can see through the gaps in the fence.

A fence occupies the center space of blocks and automatically connects to any solid block that is placed next to it. Since their hitbox is smaller than a single block, it will allow a mob in the block to breathe even when submerged.

Fences can be used to hitch mobs with a lead.

Fuel
When used as a fuel in a furnace, a fence lasts 15 seconds (or 1.5 items).

Trivia

 * If a carpet is placed on top of a fence, a player can jump onto the carpet, while mobs cannot (and won't even try). This is safer than a fence gate that might be left open, but it also can't be opened to mobs short of breaking it.
 * If you try to use an item with a right-click function while looking at a fence, the item will not perform its function but will instead appear to be attempting to mine the fence. The fence will never break from this "mining".
 * Getting hit by someone else (or shooting yourself with a knockback enchanted bow while sprinting forwards) while in midair can cause the knockback to propel you over the fence.