Differences between OUTPUT and APPEND modes in QBASIC

Output Mode		Append Mode
The existing records are deleted when program is re-executed.		The new records are added from end of file, if the program is re-executed.
The record pointer is always at the top of the file.		The record pointer remains at the bottom of the file.
The file structure is defined in each execution.		The file structure is defined at the first time execution ony.

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