Q:

Why is there a "packages" folder and how to make it work?

I have a WebSite project in VS2010. Folder structure is like:
../packages
../Website
../Website.DataAccess
etc.

I'm trying to open website by opening root folder in VS2010/Open Website. But when I do, it seems to have missing all the references, for example System.Web.Helper, System.Web.Mvc etc.
Error messages like:

Could not load file or assembly 'System.Web.Helpers, Version=1.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35' or one of its dependencies. The system cannot find the file specified.    

keep showing up.
So why is there even this folder "packages"? Should it automatically let me open website project without worrying about all the references/assemblies? 
Is there anything I should do to make the WebSite see the "packages" folder and use it, so I can build this WebSite?
EDIT 1:
Also, when trying to install new package from nuget console: install-package system.web.helpers
I get error message: The current environment doesn't have a solution open.
Since this is a WebSite, I don't have a Solution file. Anyway, seems a bit weird to me, that solution file is needed.

A:

You may be talking about the NuGet packages folder which is created to store the links to the packages you have installed from the NuGet Package Manager.

Go to nuget.codeplex.com and click this button:

A:

You need to install the NuGet Visual Studio extension to begin with. You can get it directly within Visual Studio by going to Tools -> Extension Manager and searching online for NuGet - then installing it.
Once installed, you can manage the packages through it - right click on the project node in Solution Explorer and select Manage NuGet Packages... to get the UI.
Check out the answers on How do I get NuGet to install/update all the packages in the packages.config? for details.

