Files

File is an object that contains either a set of related records handled as a group or a stream of data. One of the most common types of files that contains records is the database file. A document is the type of file that contains only a stream of data. There are different type of files on the system as follows:
1.  Physical file
2.  Logical file
3.  Display file
4.  Printer file
5.  Tape file
6.  Diskette file
7.  Message file
8.  Save file
9. Database Files
  1. Physical file that contains data records or source statements
  2. Logical file that contains access information for data.
  • Device file describes the operational characteristics of a Physical hardware device
  • Five types of device files - tape , printer, diskette, communication (message) and display
  • A file is logically divided into records and records into fields. A field cannot be subdivided