lt.<P>

Unfortunately, there is a horrendous variety of executable file formats
even among free Unix-like PC-based OS's - generally a different format for
each OS.  Most of the relevant free OS's use some variant of a.out format,
but some are moving to ELF.  It is highly desirable for boot loaders not to
have to be able to interpret all the different types of executable file
formats in existence in order to load the OS image - otherwise the boot
loader effectively becomes OS-specific again.<P>

This standar