SQL*Plus file command allow you to execute commands (or programs) stored in an external file, input or output data from/to a file, and save SQL commands typed during current session.
Some SQL*Plus file commands are:
* SAVE filename. This allows you to save buffer contents into a file.
* START filename. This allows you to execute a batch of SQL statements stored in a file.
* SPOOL filename. This allows you save SQL statements together with their outputs to a file.
* GET filename. This retrieve a file and places it into the buffer.
* @ filename. This allows you to execute a PL/SQL procedure(s) stored in a file.