Shell Programming...
Just Enough to Write CGI Programs. . .
 The Unix Shell
(Unix) Shell programs are an effective way to 'batch' common routines. In
their simplest form:
- a file is created with the desired commands, 
 executed
 - Specification of the type (format) 
of the
 output 
 - The code that does the actual work which may include:
        - Retrieving System 
Variables s uch as a UserID
        
 - Retrieving and Formatting Text such as a list of files
        
 - Formatting and Output of Data