Charles Montgomery Burns, usually just known as Mr. Burns, is the owner of Springfield Nuclear Power Plant and therefore the boss of Homer.  Mr. Burns is pure evil and most jokes are related to his age and his constant references to the past due to the fact the guy is over 100.

Mr. Burns Quotes

Labor Inspector: This plant violates every labor law in the book. We found a missing Brazilian soccer team working in your reactor core!
Mr. Burns: That plane crashed on my property!

Mr. Burns: Oh, and one more thing: you must find the jade monkey before the next full moon.
Smithers Actually sir, we found the jade monkey. It was in your glove compartment.
Mr. Burns: And the road maps, and ice scraper?
Smithers: They were in there too, sir.
Mr. Burns: Excellent! It's all falling into place...

The Simpsons Quotes

Homer: (Wearing glasses) The sum of the square roots of any two sides of an isosceles triangle is equal to the square root of the remaining side!
Man: (From inside a bathroom stall.) That's a right triangle, you idiot!
Homer: D'oh!

Labor Inspector: This plant violates every labor law in the book. We found a missing Brazilian soccer team working in your reactor core!
Mr. Burns: That plane crashed on my property!