Sets 1, 2 and 3 represent the operation of single, double and triple buffering, respectively, with vertical synchronization (vsync) enabled. In each graph, time flows from left to right. Note that 3 shows a swap chain with three buffers; the original definition of triple buffering would throw away frame C as soon as frame D finished, and start drawing frame E into buffer 1 with no delay. Set 4 shows what happens when a frame (B, in this case) takes longer than normal to draw. In this case, a frame update is missed. In time-sensitive implementations such as video playback, the whole frame may be dropped. With a three-buffer swap chain in set 5, drawing of frame B can start without having to wait for frame A to be copied to video memory, reducing the chance of a delayed frame missing its vertical retrace.
In computer science, multiple buffering is the use of more than one buffer to hold a block of data, so that a "reader" will see a complete (though perhaps old) version of the data instead of a partially updated version of the data being created by a "writer". It is very commonly used for computer display images. It is also used to avoid the need to use dual-ported RAM (DPRAM) when the readers and writers are different devices.
