Roger Waters wrote this about Mary Whitehouse, a British woman who led a movement to keep sex off TV. He felt Whitehouse had no right to decide what other people should watch.
Along with dogs and sheep, pigs are one of 3 animals represented on the album. The pigs represent people, like Whitehouse, who feel they are the moral authorities. The sheep are the people who obey the pigs and believe that it is the "Christian" thing to do and are just your normal, hard working innocent bystanders. Dogs are people who are against the pigs and are back stabbers. (thanks, Lee - Durham, NC)
The album cover shows a giant inflatable pig drifting above a London power station. During the shoot, the pig broke free, where it caused chaos as it floated near Heathrow airport. It went up about 18,000 feet before coming down in a farm in Kent. They never did get the shot, and ended up compositing 2 pictures for the cover.
The giant, inflatable pig became a part of Pink Floyd's live show, where it was brought out for this song. The pig became a point of contention when the band toured without Roger Waters - the new inflatable pig had testicles, which some fans interpreted as a stab at Waters.
When the band toured without Roger Waters in 1987, they used an inflatable pig that was altered to have a huge penis. The band claimed they did it because Waters had the original idea for the pig and they did not want him to sue for copyright infringement. Waters was furious when the band continued on after he left.
On the TV show South Park, Eric Cartman has quoted the line from this song, "Ha-ha, charade you are" on several episodes. (thanks, Bert - Pueblo, NM)
OK, more on the pig - but this one is good: Roger Waters used an inflatable pig when he performed at the 2008 Coachella festival, this time the pig was emblazoned with the word "Obama" as Waters wanted to support the US presidential candidate. When Waters performed this song, the pig was released on cue, but broke free and floated away. Festival organizers offered lifetime passes and $10,000 cash for the pig's safe return. In was found a few miles away in two plastic heaps by some surprised homeowners in La Quinta. (thanks, Bertrand - Paris, France)