View any document in your windows forms application C#

Do you want to view/display a document (e.g. PDF, Word, Excel, PPT) in your windows forms application?
It doesn't matter if MS Office or any PDF reader is installed on your machine or not. All you have to do is to implement this API in your (new or existing) .NET application.
Have a look at following helpful resources:

• How to view a file in windows form application?
• Possibility of Viewer Integration with Windows Forms app