The 1.2 kernel was the final PC-only Linux kernel. The source distribution
for Linux 1.2 included partially implemented support for SPARC, Alpha, and
MIPS CPUs, but full integration of these other architectures did not begin until
after the 1.2 stable kernel was released.
The Linux 1.2 release concentrated on wider hardware support and more
complete implementations of existing functionality. Much new functionality
was under development at the time, but integration of the new code into the
main kernel source code had been deferred until after the stable 1.2 kernel had
been released. As a result, the 1.3 development stream saw a great deal of new
functionality added to the kernel.