title: Advice on layered architecture (Win Forms + WinService; WCF; LINQ to SQL)
body: <p>I'll try to explain as briefly as possible:</p>
  
  <p><strong>C#.Windows application for categories and descriptions of files.</strong></p>
  
  <p><strong>Windows Forms</strong> - for the user</p>
  
  <p><strong>A library I want to be saved for future usage</strong> - I got nice algorithms for tasks with XML,Files,strings. In this case they are to serve the WF, but i don't want to keep them in the Form classes. I want to have them as a separate library with namespaces and classes in it. But I don't know what type of project or addition to the whole VS "Solution" that has to be. </p>
  
  <p><strong>Windows Service</strong> - get notifications on file changes and updates the same db the WF is using.</p>
  
  <p><strong>LINQ to SQL</strong> - for the data access</p>
  
  <p><strong>WCF</strong> - I am just throwing that here, because it seems that I need to use it(answer from a previous related topic) : <a href="https://stackoverflow.com/a/15998122/1356685">https://stackoverflow.com/a/15998122/1356685</a></p>
  
  <p>SO...yeah...architecture, architecture. Any guideline for a good architecture in my case is welcomed. Now I know in these conversations people start throwing terms like: "business logic","persistence layer","model layer" and what not. However I don't quite understand them, so please be specific.</p>
  
  <p>Thanks in advance for the help !</p>