 Foremost among these for many years was the BBC's Sir Peter O'Sullevan, known as 'the voice of racing', who commentated on 50 Grand Nationals.Channel 4's most recognisable racing figure was John McCririck, famed for his eccentric dress sense and use of the bookmakers' sign language 'tic-tac'.Other notable presenters of Channel 4's coverage included Derek Thompson, John Francome, John Oaksey and Brough Scott.