<screenname> was the name of the screen that the programmer assigned to the program. <filename> was the file name to be accessed in the data dictionary. Whether the items in the file would all fit in the screen would be determined by how many items and the size of them. If they didn't all fit, the program would have to be modified to eliminate unneeded items, change the size of items to some other size, etc. But, for a file with only a couple of items in it, it is quick and easy to generate a screen for data entry, deletion, or to simply look up data by an index.