What is file in data hierarchy?

A file is a group of related records. [Note: More generally, a file contains arbitrary data in arbitrary formats.In some operating systems ,a file is viewed simply as a sequence of bytes— any organization of the bytes in a file, such as organizing the data into records, is a view created by the programmer.] It’s not unusual for an organization to have thousands or even millions of files, some containing billions or even trillions of characters of information.