Topic summary
Linux framebuffer

Abstraction layer for Linux kernel to show graphics on the system console Knoppix booting on the framebuffer The framebuffer subsystem in the Linux kernel fbdev is used to show graphics on a computer monitor, typically on the system console. It was designed as a hardware-independent API to give user space software access to the framebuffer (the part of a computer's video memory containing a current video frame) using only the Linux kernel's own basic facilities and its device file system interface, avoiding the need for libraries like SVGAlib which effectively implemented video drivers in user space. In most applications, fbdev has been superseded by the Linux Direct Rendering Manager (DRM) subsystem, but as of 2022, several drivers provide both DRM and fbdev APIs for backwards compatibility with software that has not been updated to use the DRM system, and there are still fbdev drivers for older (mostly embedded) hardware that does not have a DRM driver. Applications There are three applications of the Linux framebuffer: An implementation of text Linux console that doesn't use hardware text mode (useful when that mode is unavailable, or to overcome its restrictions on glyph size,