To
            aid you in the process of maintaining multiple-file applications,
            VLISP provides a construct called a project. A VLISP project contains
            a list of AutoLISP source files, and a set of rules on how to compile
            the files. Using the project definition, VLISP can do the following:
         
         
            - Check
               which .lsp files in your application
               have changed, and automatically recompile only the modified files.
               This procedure is known as a Make procedure.
            
- Simplify
               access to source files by listing all source files associated with
               a project, making them accessible with a single-click.
            
- Help
               you find code fragments by searching for strings when you do not know
               which source files contain the text you're looking for. VLISP limits the
               search to files included in your project.
            
- Optimize
               compiled code by directly linking the corresponding parts of multiple
               source files.
            
Before discussing how to define and use VLISP
            projects, it may help to introduce file types used in VLISP.