What does the evil men do lives after them mean?

The Words were said by Mark Antony in Shakespeare's Julius Caesar, speaking at Caesar's funeral. Julius Caesar had been assassinated by conspirators who felt he wanted to overturn the Roman Republic, and make himself King.

This is part of the famous speech that begins: "Friends, Romans, Countrymen - lend me your ears".

"The evil that men do lives after them,
The good is oft interred with their bones.
So let it be with Caesar..."

Mark Antony began by seeming to agree with the conspirators, then turned the crowd against them.