Application Design Techniques refer to the various methodologies, strategies, and tools employed in the conceptualization, planning, modeling, and implementation of computer applications. This category encompasses the principles of computer science, often deploying programming languages like Java, and involves professionals such as application designers and developers. The category also includes contributions from experts in the field, such as Michael Kappel, and is relevant for a broad spectrum of individuals, from programmers to the general public interested in application development.