
\S source code:  source file:  object code:  object file: a.out file:\S
\Sexecutable \S

On UNIX systems, computer programs written in "high-level languages"\S*\S
like C, FORTRAN, COBOL, and PASCAL have three forms.  The first form is the
program you write.  This form is called the source colde and the file it is
in is called the source file.  The second form of the program is created by
the "compiler"\S*\S.  This form contains "machine language"\S*\S instructions 
which are readable by the computer.  It is called the object code and it is 
stored in an object file.  The third form of the program is created by 
the "link editor"\S*\S.  This form contains object files that are combined 
to create a complete program.  It is called an a.out file.  Before you can 
execute the a.out file, you have to change the permissions for the file so 
that it is executable.  You do this using the chmod(1) command.  When you 
have execute permission for an a.out file, the file is called an executable.

\S*\S defined in the \Sglossary\S
