Who played Daryl Dixon in 'The Walking Dead'?

In which TV series is Damon Salvatore a main character? Who played Richard Castle in 'Castle'? Who played Rick Grimes in 'The Walking Dead'? In which TV series is Rick Grimes a main character? In which TV series is Daryl Dixon a main character? Who played Negan in 'The Walking Dead'? In which TV series is Negan a main character? Who played Nucky Thompson in 'Boardwalk Empire'?