B-roll is secondary footage in an online news video that provides a visual explanation of an issue or event and helps to tell the story. A video about a new fire station, for example, might include the fire chief talking about how it will improve safety in a neighborhood. The video editor might use B-roll of workers finishing the station to "cover" part of the interview with the fire chief, so that the Web user hears the fire chief while seeing the fire station's completion. B-roll lends variety and visual detail to news video and provides relief from talking heads.