The software is very easy to use and intuitive.

HelpNDoc is very easy to install and use. It exports to a number of different formats including CHM and PDF. I have authored help documents using this software that are linked to VB.NET WinForms code, and the interaction between .NET and the HelpNDoc CHM works perfectly to provide in-application context sensitive help. For anyone who needs to generate PDF manuals or CHM help files, this is the software I recommend you use.

I like having the ability to build help files in many different formats. For example, if I want to call my help documentation from a windows application that I wrote - I generate a .chm file. I can also generate the code required to link to a specific help topic with the help file.