I am new to Mathematica but for several years I have been using Delphi for mathematical modeling. In Delphi, applications are called Projects and a project will comprise several Units. I created a unit that I named Toobox. It contained many functions and procedures created by me but useful in a wide variety of projects. By adding Toolbox to any Project the complete contents of Toolbox were made available even though I might wish to use just a single function or procedure. I would like to accomplish the same with Mathematica and this is my solution - so far. I have created a Notebook called Toolbox that I am filling with functions and blocks of text. When I need a function, for example, I copy its cell from Toolbox and paste it into whatever notebook needs it. Is there a better way of doing this? My solution seems cumbersome compared to my Delphi experience.
Take a look at the following threads here on this site:
What you want to create is a Package.