extra data copy through itself of the main memory buffer client-to-compositor-to-GPU method, resulting in faster graphics performance, and is therefore the preferred one. The compositor can further optimize the composition of the final scene to be shown on the display by using the same hardware acceleration API as an API client. When rendering is completed in a shared buffer, the Wayland client should instruct the compositor to present the rendered contents of the buffer on the display. For this purpose, the client binds the buffer object that stores the rendered contents to the surface object, and sends a "commit" request to the surface, transferring the effective control of the buffer to the compositor. Then the client waits for the compositor to release the buffer (signaled by an event) if it wants to reuse the buffer to render another frame, or it can use another buffer to render the new frame, and, when the rendering is finished, bind this new buffer to the surface and commit its contents. The procedure used for rendering, including the number of buffers involved and their management, is entirely under the client control. Comparison with other window systems Differences between Wayland and X There are several differences between Wayland and X with regard to performance, code maintainability, and security: Architecture The composition manager is a separate, additional feature in X, while Wayland merges display server and compositor as a single function. Also, it incorporates some of the tasks of the window manager, which in X is a separate client-side process. Compositing Compositing is optional in X, but mandatory in Wayland. Compositing in X is "active"; that is, the compositor must fetch all pixel data, which introduces latency. In Wayland, compositing is "passive", which means the compositor receives pixel data directly from clients. Rendering The X server itself is able to perform rendering, although it can also be instructed to display a rendered window sent by a client. In contrast, Wayland does not expose any API for rendering, but delegates to clients such tasks (including the rendering of fonts, widgets, etc.). Window decorations are to be rendered on the client side (e.g., by a graphics toolkit), or on the server side (by the compositor) with the opt-in xdg-decoration protocol, if the compositor chooses to implement such functionality. Security Wayland isolates the input and output of every window, achieving confidentiality, integrity and availability for both. The original X