Sooner or later, every VB programmer needs to be able to plugin to the native Windows framework to perform some task which isn’t possible with their development platform. The KPD-Team from Belgium, offers a nicely documented and searchable database of over 900 useful functions which make up the API-Guide:

So, if (like us) you’re still occasionally having to support applications which haven’t been migrated to the .NET Framework, you’ll find the API-Guide an indispensable starting point to programmatically accessing the Windows user interface, network communications, numeric algorithms, data access, cryptography and more.