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+The SeaBIOS code can be built using standard GNU tools. A recent Linux
+distribution should be able to build SeaBIOS using the standard
+compiler tools.
+
+Building SeaBIOS
+================
+
+First, [obtain the code](Download.md). SeaBIOS can be compiled for
+several different build targets. It is also possible to configure
+additional compile time options - run **make menuconfig** to do this.
+
+Build for QEMU (along with KVM, Xen, and Bochs)
+-----------------------------------------------
+
+To build for QEMU (and similar), one should be able to run "make" in
+the main directory. The resulting file "out/bios.bin" contains the
+processed bios image.
+
+One can use the resulting binary with QEMU by using QEMU's "-bios"
+option. For example:
+
+`qemu -bios out/bios.bin -fda myfdimage.img`
+
+One can also use the resulting binary with Bochs. For example:
+
+`bochs -q 'floppya: 1_44=myfdimage.img' 'romimage: file=out/bios.bin'`
+
+Build for coreboot
+------------------
+
+To build for coreboot please see the coreboot build instructions at:
+<http://www.coreboot.org/SeaBIOS>
+
+Build as a UEFI Compatibility Support Module (CSM)
+--------------------------------------------------
+
+To build as a CSM, first run kconfig (make menuconfig) and enable
+CONFIG_CSM. Then build SeaBIOS (make) - the resulting binary will be
+in "out/Csm16.bin".
+
+This binary may be used with the OMVF/EDK-II UEFI firmware. It will
+provide "legacy" BIOS services for booting non-EFI operating systems
+and will also allow OVMF to display on otherwise unsupported video
+hardware by using the traditional VGA BIOS. (Windows 2008r2 is known
+to use INT 10h BIOS calls even when booted via EFI, and the presence
+of a CSM makes this work as expected too.)
+
+Having built SeaBIOS with CONFIG_CSM, one should be able to drop the
+result (out/Csm16.bin) into an OVMF build tree at
+OvmfPkg/Csm/Csm16/Csm16.bin and then build OVMF with 'build -D
+CSM_ENABLE'. The SeaBIOS binary will be included as a discrete file
+within the 'Flash Volume' which is created, and there are tools which
+will extract it and allow it to be replaced.
+
+Distribution builds
+===================
+
+If one is building a binary version of SeaBIOS as part of a package
+(such as an rpm) or for wide distribution, please provide the
+EXTRAVERSION field during the build. For example:
+
+`make EXTRAVERSION="-${RPM_PACKAGE_RELEASE}"`
+
+The EXTRAVERSION field should provide the package version (if
+applicable) and the name of the distribution (if that's not already
+obvious from the package version). This string will be appended to the
+main SeaBIOS version. The above information helps SeaBIOS developers
+correlate defect reports to the source code and build environment.
+
+If one is building a binary in a build environment that does not have
+access to the git tool or does not have the full SeaBIOS git repo
+available, then please use an official SeaBIOS release tar file as
+source. If building from a snapshot (where there is no official
+SeaBIOS tar) then one should generate a snapshot tar file on a machine
+that does support git using the scripts/tarball.sh tool. For example:
+
+`scripts/tarball.sh`
+
+The tarball.sh script encodes version information in the resulting tar
+file which the build can extract and include in the final binary. The
+above EXTRAVERSION field should still be set when building from a tar.
+
+Overview of files in the repository
+===================================
+
+The **src/** directory contains the main bios source code. The
+**src/hw/** directory contains source code specific to hardware
+drivers. The **src/fw/** directory contains source code for platform
+firmware initialization. The **src/std/** directory contains header
+files describing standard bios, firmware, and hardware interfaces.
+
+The **vgasrc/** directory contains code for
+[SeaVGABIOS](SeaVGABIOS.md).
+
+The **scripts/** directory contains helper utilities for manipulating
+and building the final roms.
+
+The **out/** directory is created by the build process - it contains
+all intermediate and final files.
+
+When reading the C code be aware that code that runs in 16bit mode can
+not arbitrarily access non-stack memory - see [Memory
+Model](Memory_Model.md) for more details. For information on the major
+C code functions and where code execution starts see [Execution and
+code flow](Execution_and_code_flow.md).