In this lecture note, we move along the direction of developing desktop applications, and we are going to introduce a technology called the Windows Presentation Foundation (WPF). WPF was first released as a part of .NET 3.0 in 2006. Since then, of course, it gets extended and updated from one .NET release to another. In the Sections II-II, we are going to give an introduction into the world of WPF, and then, between the Sections III and XIV, this knowledge will be deepened step by step. If the reader possibly drew to developing for web or for mobile devices, then it would be really worth to get familiar with WPF, since Silverlight is a fundamental technology on either web or on Windows Phone platform; Silverlight, which came out as a subset of WPF (and was called WPF/E=„WPF/Everywhere”), is based on the same foundation and solutions. In the lecture note, we are going to touch upon the topic of database programming as well, since each graduate programmer must possess at least basic familiarity with this topic. We are going to introduce the corresponding .NET technology, Language Integrate Query (LINQ) in the Sections XV-XVII, and we will combine it with WPF in our examples.