What is the fine-grained topic of the following text: To make Microsoft® Office® applications available to Microsoft Visual Studio® .NET developers, Microsoft has created several primary interop assemblies (PIAs) that contain the official description of commonly-used Microsoft Office type libaries for applications such as Microsoft Access®, Microsoft Powerpoint®, Microsoft Excel®, Microsoft Word®, and so on. Only return the topic.
Microsoft's creation of primary interop assemblies for Office applications for Visual Studio .NET developers