The most popular version of Linux by far is the x86 version for PC-compatible computers. PCs are inexpensive and can serve as both a development host and a target. Most of the Linux developers around the world have PCs and develop for it first. Many embedded systems use x86 processors. There are many variants x86 from very fast to very low power. A complete PC-compatible computer can fit on a single chip. For some embedded developers an x86 version of Linux is all that is needed. But in some cases an x86 processor is not the best choice. In the ultra low power range other processors such as the ARM® or Hitachi SH processors can provide the same performance level and use less power. For some applications micro-controllers with PowerPC® CPU cores, for instance, have the right built in I/O and coprocessors to reduce hardware costs. For some performance ranges there are MIPS processors that have a better prices performance ratio than any x86 processor. So the embedded microprocessor market is still fragmented. In fact it is as fragmented as it ever was and there is no sign of consolidation.

The good news is that Linux has been ported to many different embedded microprocessors including the PowerPC, MIPS, ARM, StrongARM®, and SH. The bad news is that these ports of Linux do not yet enjoy the amount of third-party software that the x86 port of Linux has. Now that there are vendors for embedded Linux making periodic releases of their Linux distributions for non-x86 platforms, the situation should improve. A growing number of third-party software vendors have pledged support for Linux on a variety of embedded processors. But customers provide the strongest motivation. Inquiries about the availability of an application, or protocol stack, for Linux on a specific processor may speed the porting processes.