In Fortran's I/O system, data is stored and transferred among files. All I/O data sources and destinations are considered files.
Devices such as the screen, keyboard and printer are external files, as are data files stored on a device such as a disk.
Variables in memory can also act as a file on a disk, and are typically used to convert ASCII representations of numbers to binary form. When variables are used in this way, they are called internal files.
Topics covered in this section include the following:
Logical Devices
Types and Forms of I/O Statements
File Organization, File Access and File Structure
Internal Files and Scratch Files
File Records, including Record Types, Length, Access, and Transfer
Using I/O Statements such as OPEN, INQUIRE, and CLOSE
For information on techniques you can use to improve I/O performance, see Improving I/O Performance.