Microsoft Visual Studio (VS for short) consists of a series of development kit products produced by Microsoft (written in C++ and C#), and is currently the most popular IDE (integrated development environment) for developing applications on Windows platform. As of writing this post, its latest release is Visual Studio 2019, based on Microsoft .NET Framework 4.7.

Not My Fault (AKA: NotMyFault) is a driver-level system debugging tool, developed by Microsoft's Sysinternals group, used to artificially make system crash, memory leak, frozen screen and blue screen in order to reconstruct, analyze and debug the potential problems in a computer.

Microsoft WorldWide Telescope (WWT for short, now called AAS WorldWide Telescope) is a free and open-source virtual, visualized digital planetarium project (including application, data and cloud services) for both web browser (based on HTML5 and WebGL) and Windows desktop. It was originally created by Microsoft Research in 2002, and is now managed by the American Astronomical Society, and supported by grants from the Gordon and Betty Moore Foundation and National Science Foundation.

Skype is currently the world's most popular free HD instant messaging software (and VoIP) for all kinds of desktop and mobile platforms. Low system resource requirement, high-quality voice communication and high stability have won its hundreds of millions of users around the world. After acquired by Microsoft in 2011, it became an independent department of Microsoft. And in 2013, if finally replaced Microsoft's own instant messaging tool MSN. In 2014, it released an embedded web version.

PIDKey is a lightweight and free database-based tool mainly used to test the validity of Microsoft Windows/Office/Visual Studio (and more) product keys in batch, made by Ratiborus and his friends from Russia. With it, we can say goodbye to the huge VAMT (Volume Activation Management Tool).