Source_Format

 Source code can be in free, fixed, or tab format.  Fixed or tab
 forms must not be mixed with free form in the same source program,
 but different source forms can be used in different source
 programs.

 All source forms allow lowercase characters to be used as an
 alternative to uppercase characters.

 More than one statement (or partial statement) can appear on a
 single source line if a statement separator is placed between the
 statements.

 The statement separator is a semicolon character (;).  Consecutive
 semicolons (with or without intervening blanks) are considered to
 be one semicolon.  If a semicolon is the last character on a line,
 or the last character before a comment, it is ignored.

Additional information available:

Free_Form       Fixed_and_Tab_Format            Example