Difference between Addin and VSPackage in Visual Studio extensibility?

Question

What's diff in term of functionality are there between addins and Visual Studio Packages ?

Answer 1

This article is a good place to start: http://msdn.microsoft.com/en-us/library/bb330853.aspx

VSPackages are the 'first class citizens' in the IDE. Much of the core IDE functionality is actually supplied via packages. This is how Microsoft itself adds functionality to Visual Studio (i.e. new tools, languages, etc...).

Addins are limited in what they can do. Generally, they are restricted to using only the DTE automation object model to accomplish their tasks. The advantage is that it's usually simpler to do what you need this way, and the templates are included "in the box".

In general, we recommend that folks extend the IDE via VSPackages for new projects. You'll need to download the Visual Studio SDK to get started.