World Wrestling Entertainment hasn't always been known as WWE. From 1979 to 2002, the wrestling franchise was known as World Wrestling Federation or WWF for short. The organization changed its name following a lawsuit by the World Wildlife Fund, which also goes by WWF.
The two actually first settled in 1994, according to the Guardian, on the terms that the WWE would cut back on the use of the acronym, but in 2002, a UK court found that the original agreement had been breached and thus, the WWE was born out of necessity.