Kay De (KDE), a project to develop a desktop (graphical user interface that the operating system is placed), and other related software. This Desktop, more on Unix, etc., Linux, SMS, etc., AIX, and Solaris, which runs lately, it can be used on Windows and Mac OS also installed.

When, in 1996, Matthias, Austria (Matthias Ettrich) , to bring. At that time, some of the features of desktop Unix for his problem. such that none of its programs, the appearance and the function of coordination in this regard. At the same time,, to build a set of applications were not, and build a desktop that all user needs to fix its bid. Her easy-to-use from desktop also the criterion to build the alliance and thus the project, Kay, was born.