Widebody twin engine medium haul airplane built by Airbus through the late 70's, 80's, 90's and marginally in early 2000's.
It was made to compete with DC10 and L1011 by offering a smaller but more cost efficient plane.
Although not revolutionary it was a success thanks to its cautionnary approach using mainly reliable and proven parts like GE CF6 engine and building on the experience of companies merged in Airbus consortium.
Today it isn't used much in commercial passenger flight but is still widely used as freighter.
Look at that A330 !
You are wrong that is a A300.