Subtitling is the textual representation of spoken language in a video in a way that permits the rendition of the text on screen. The service may include ‘spotting’, i.e. the synchronisation of the subtitles and the video. Subtitles can be provided in the source language of the video only, or in one or several other languages, and they are delivered together with time codes indicating the exact time at which a subtitle is displayed and how long it is visible on the screen.