Online-Help

Technical Documentation
Anyone who creates a technical product, be it in the form of hardware or software, cannot avoid creating Technical documentation. And vice versa: Anyone who has ever had to operate, repair, maintain or service technical products of a more complex nature has probably consulted a Technical Documentation.

Context sensitive help in C# and CHM files
A good online help avoids support requests. Ideally, he gets the answer already in the help. So that the user does not have to search long, there is the possibility to navigate the user directly to the desired place, e.g. to the help of a certain dialog.