He owns Springfield's Nuclear Power Plant and is portrayed as the prototype of an early capitalist exploiter, and is always a little behind times (for example, he thinks Prussia still exists). He is almost always accompanied by his assistant Waylon Smithers.
Due to his status as the town's leading (and perhaps only) plutocrat, Mr. Burns is able to do whatever he wants with little or no consequences.
The character of Burns is also patterned after Howard Hughes.