Editing Multiple buffering (section)

=== Software double buffering ===
A software implementation of double buffering has all drawing operations store their results in some region of system [[Random Access Memory|RAM]]; any such region is often called a "back buffer". When all drawing operations are considered complete, the whole region (or only the changed portion) is copied into the [[video RAM]] (the "front buffer"); this copying is usually synchronized with the monitor's [[raster graphics|raster]] beam in order to avoid tearing. Software implementations of double buffering necessarily require more memory and CPU time than single buffering because of the system memory allocated for the back buffer, the time for the copy operation, and the time waiting for synchronization.

[[Compositing window manager]]s often combine the "copying" operation with "[[compositing]]" used to position windows, transform them with scale or warping effects, and make portions transparent. Thus, the "front buffer" may contain only the composite image seen on the screen, while there is a different "back buffer" for every window containing the non-composited image of the entire window contents.