Standard

 
 A Fortran line is divided into fields for the required information.
 Each column represents a single character.


  COLUMN    FIELD
  ------    -----
      1     Indicator: Comment(C,c,*,!,blank) or Debug(D,d)
    1-5     Label (any decimal integer except zero)
      6     Indicator: Continuation of statement (any character
                  except zero or space)
   7-72     Statement Field (up to column 72)
  73-80     Sequence Number (optionally to column 132 -- ignored)

Tab 

 A Fortran line is divided into fields for the required information.
 Each column represents a single character.  You cannot specify a
 sequence number field using this method of coding.


  COLUMN   FIELD
  ------   -----
  (before tab)
    1      Indicator: Comment(C,c,*,!,blank) or Debug(D,d)
  1-5      Label (any decimal integer except zero)
  (after first tab)
    6      Indicator: Continuation of statement (any digit 1-9)
  (after second tab)
           Statement Field (up to column 72)


 Tabs are treated as single characters.