Pigs are passive mobs that are the source of porkchops, and are a renewable source of food. They are 0.875 blocks tall, 0.625 blocks wide and 1.25 blocks long. 
Usage: Each pig will drop 0 - 2 raw porkchops upon death. Since Beta 1.5, Pigs that die while on fire will drop 0 - 2 cooked porkchops instead. 
Behavior: Pigs roam the Overworld in groups of 3 - 4. When they encounter obstacles, they will often try to surmount them by hopping up and down. They make no attempt to stay out of water, bobbing up and down to stay afloat. Pigs have been described as the "stupidest mob" due to their inefficient, sometimes comical, pathing. When leading them with wheat they will often become stuck on the opposite side of a block rather than walking around it. 
By right-clicking on a pig while holding a saddle, a player can ride it. However, the movement of the pig cannot be controlled by the player. Riding a pig off a cliff is one of the more unusual and challenging achievements in Minecraft. 
Pigs tend to move more often, but in smaller strides, towards the North-East, without any other variables coming into play.
Breeding: Like all passive mobs, excluding squid and villagers, pigs can be bred using Wheat. If you right click a baby pig with a saddle, you will find yourself riding the baby pig. 
Bugs: If you save and quit while riding a pig the "Saving Chunks" bar will not fill up properly and can stop filling up and appear to be frozen before it suddenly opens the main menu (without the bar filling up any more). 
In single player, monster spawners contain a spinning miniature mob of the type that will be spawned. On SMP, on the other hand, monster spawners always contain a miniaturized pig, no matter what mob they spawn.[3] 
When a pig that is being ridden is killed, it will not drop the saddle. 
In 1.8 and 1.9 there is a bug that makes the pigs spawn too much. 
Trivia: For some reason, all Mob Spawners found in SMP have pigs inside them instead of whatever creature they actually spawn, with the singular exception of the Cave Spider. 
In addition, any Spawner placed by a Player will be a Pig Spawner on default. It may be altered via Mods later on. 
Pigs have a separate "armor" file (the saddle), but do not spawn with it. 
If you manage to get a pig with a saddle into a minecart, the pig will boost the minecart. 
By putting a pig with saddle in a minecart, and getting it off the tracks, it acts like a car. But with opposite controls. 
If a ridden pig is hit by lightning, it still turns into a Zombie Pigman. The Player will receive 2 and a half hearts damage and be knocked off the mob. 
It takes one full Minecraft day or 20 minutes for baby piglets to become fully mature pigs. 
Baby Pigs that get hit by lightning turn into Zombie Pigmen, the same as normal pigs do. 
When the player is riding a pig, the player can still sneak. 
One of the splashes which shows up on the title screen reads "Ride the pig!" (Possibly a reference to the TV show Invader Zim). 