Program Translation
Here is a picture that shows what usually happens with programs
written in "C" (Java is different; it will be discussed in the next chapter.)
Here is a review of what goes on:
- The source file is created using a text editor.
    
    - It contains instructions in a high level language.
 
    - It contains bytes that hold characters.
 
    
 
- The source file is kept on the hard disk.
 
- The source file can not be run by the processor.
 
- A translator (compiler) program can translate the source file into an executable file.
    
    - The source file remains unchanged; a new executable file is created.
 
    - A translator is used for programs written in
        a specific high level language (like "C") and
        a specific processor type (like "Pentium"), 
        and only runs under a specific operating system (like "Windows".)
 
    
 
- The executable file is also kept on hard disk.
 - To run the program, the operating system is told to copy the executable file
    into main memory and to start it running.
 
The above is what goes on with most languages: Ada, Pascal, C, C++, FORTRAN and others.
Java adds a few more steps,
which will be discussed in the next chapter.