In QBASIC/QuickBASIC the IDE is not file-based. By default it only shows the content of the current sub routine, as opposed to the content of a file. If you wa

In QBASIC/QuickBASIC the IDE is not file-based. By default it only shows the content of the current sub routine, as opposed to the content of a file. If you want to look at / edit a different subroutine you open the sub routine selection dialog and select the one you want which then becomes the currently displayed one. In the same way, if you want to add a new subroutine to the program you open the subroutine creation dialog, give it a name and then the IDE automatically makes the newly created subroutine the currently displayed one. I.e. you are only ever looking at one subroutine at a time. Screenshot of the subroutine selection dialog: http://synapticnulship.com/blog/wp-content/uploads/2011/01/qb-subs-shk-c.png http://synapticnulship.com/blog/wp-content/uploads/2011/01/q... Sounds limiting to programmers used to modern IDEs where you usually look at multiple functions at once, but I remember it fondly. There is something to be said for completely focusing on one sub routine at a time and for the IDE presenting your program that way, while everything is actually stored in one big file.