Often the devices we use now come with someform of bootstrap (often annoyingly complicated,which gets in the way).  Older boards were sometimesbare, and we had to provide something (often annoyinglycomplicated...).  On the PC it's currently helpful tohave something that can boot from disc or ether;since it's a thankless task to write such a thing, weuse Plan 9's, and thank its authors. The current scheme on newer devices is to have a simpleprogram that can put a stripped-down Inferno kernel intoflash, and use that to boot from other devices (including over the net)as required during development. There are two distinct models for bootstrap in this directory. 	Model I Each member of the first model is represented by a self-contained directory.They are derived from various ages of Plan 9's /sys/src/boot/pc. arm1110	arm	a prefix to a gzip'd kernel to decompress it (runs after basic bootloader)pc	386	pc-specific bootstrap essentially identical to current Plan 9		and covered by the Lucent Public License; it useslibflate	-	zlib-style inflate/deflate librarympc	power	PowerPC bootstrap for FADS board derived from an older version		of Plan 9 but covered by our Inferno licence (because it came with Inferno)puma	arm	SA110 bootstrap for Teralogics Puma, also covered by the Inferno licence 	Model IIomap	purpose-built bootstrap for the OMAP processor Not all of these are being distributed.