Perl/Tk saves your favourite tools

• Objects can be interfaced as if they are a simple scalar, array, hash, or file-handles. In the main program, you think to work with a basic element, but there is more behind the scene.
• A tie translates access to the variable which represents the invisible object into calls to methods of that object.
• It is easy to create a database behind a hash later, without changing the rest of your program in more than a few lines.
• In Tk, ties are used to change the value on a Label/Entry on the moment a variable changes value. We'll see more on that.