CSM or Compatibility Support Mode is a part of UEFI Firmware and is used to make an operating system and other connected devices compatible with the UEFI. It is only used by devices when the ...
A computer’s basic input/output system (BIOS) is a program that’s stored in nonvolatile memory such as read-only memory (ROM) or flash memory, making it firmware. The BIOS (sometimes called ROM BIOS) ...