File
From Just Solve the File Format Problem
A file (meaning a computer file) is an encapsulated, persistent record of discrete (digital) data.
Nowadays, a file is typically in the form of a single stream of 8-bit byte values, where there can be any whole number of bytes. It has at least a filename associated with it, and usually other metadata, such as a last-modified timestamp. As obvious as this structure may seem to modern day computer users, many other structures, both less-flexible and more-flexible, have been used.
Files are usually managed by a filesystem.
