%BOOK_ENTITIES; ]> This document concerns the (i) Wayland architecture, (ii) Wayland model of operation and (iii) its library API. Wayland protocol specification is shown also in the Appendix. The document here is aimed at Wayland developers and who is looking for information how to program with it, but it is not meant primarily for applications developers. There have been many contributors to this document and, while this is the first edition only, many errors are expected to be found. We appreciate corrections. Yours, the Wayland open-source community November 2012