Bitplanes constitute the planar graphics architecture fundamental to Amiga computers, where image data is organized into separate memory layers with each plane containing one bit of color information per pixel. The Amiga's display hardware combines these planes to produce the final image, supporting 2^n colors from n bitplanes—up to six planes (64 colors) in OCS/ECS chipsets and eight planes (256 colors) in AGA systems. This design enabled efficient hardware scrolling by modifying bitplane pointers rather than moving data, and allowed the Copper co-processor to manipulate color registers mid-frame, though each additional plane consumed more DMA bandwidth from the shared chip memory.