on file

File \File\ (f[imac]l), n. [F. file row (cf. Pr., Sp., Pg., &
   It. fila), LL. fila, fr. L. filum a thread. Cf. {Enfilade},
   {Filament}, {Fillet}.]
   1. An orderly succession; a line; a row; as:
      (a)
      (Mil.) A row of soldiers ranged one behind another; -- in
             contradistinction to {rank}, which designates a row
             of soldiers standing abreast; a number consisting
             the depth of a body of troops, which, in the
             ordinary modern formation, consists of two men, the
             battalion standing two deep, or in two ranks.
             [1913 Webster]

   Note: The number of files in a company describes its width,
         as the number of ranks does its depth; thus, 100 men in
         "fours deep" would be spoken of as 25 files in 4 ranks.
         --Farrow.
      (b) An orderly collection of papers, arranged in sequence
          or classified for preservation and reference; as,
          files of letters or of newspapers; this mail brings
          English files to the 15th instant.
      (c) The line, wire, or other contrivance, by which papers
          are put and kept in order.
          [1913 Webster]

                It is upon a file with the duke's other letters.
                                                  --Shak.
      (d) A roll or list. "A file of all the gentry." --Shak.

   2. Course of thought; thread of narration. [Obs.]
      [1913 Webster]

            Let me resume the file of my narration. --Sir H.
                                                  Wotton.
      [1913 Webster]

   3. (computers) a collection of data on a digital recording
      medium treated as a unit for the purpose of recording,
      reading, storage, or indexing; -- such a file is typically
      accessible by computer programs by the use of a file name.
      The data may be of any type codable digitally, such as
      simple ASCII-coded text, complex binary-coded data, or an
      executable program, or may be itself a collection of other
      files.
      [PJC]

   {File firing}, the act of firing by file, or each file
      independently of others.

   {File leader}, the soldier at the front of any file, who
      covers and leads those in rear of him.

   {File marching}, the marching of a line two deep, when faced
      to the right or left, so that the front and rear rank
      march side by side. --Brande & C. 

   {Indian file}, or {Single file}, a line of people marching
      one behind another; a single row. Also used adverbially;
      as, to march Indian file.

   {On file}, preserved in an orderly collection; recorded in
      some database.

   {Rank and file}.
      (a) The body of soldiers constituting the mass of an army,
          including corporals and privates. --Wilhelm.
      (b) Those who constitute the bulk or working members of a
          party, society, etc., in distinction from the leaders.
          [1913 Webster]