Glossary A–ZLetter P
Pre-download (prefetching)
With pre-downloading, a player fetches media and schedules before they are needed and then plays them from its own storage.
The opposite is streaming, where content is only transferred during playback.
This means a campaign starting at 6 am on Monday can already be on every device on Sunday evening. Screens on mobile connections download large files at night, and playback continues even if the network drops out briefly. Many systems download new content in the background and only switch over once all files are complete and verified, so that no half-finished state appears on screen.
The player’s storage must be large enough for all scheduled content, including that for the coming days. Enough lead time is needed: anyone uploading a file five minutes before it starts risks sites with slow connections not having it in time. The management software should show whether a device has downloaded everything. Live content such as web pages, weather or television cannot be downloaded in advance. Files no longer needed should be deleted from the device automatically.