An Off Line Editor or OLE is typically a piece of (usually free) computer software, which can be used to familiarise oneself with the user interface and to learn how a certain sound or lighting desk works before you actually start work on site.
It allows you to perform some or all of the functions of a real desk to build/patch/edit shows in situations where you cannot access the desk itself. These created shows can then be saved to {typically} floppy disks which can be loaded into the real desk when needed.
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