Surprisingly, every individual comes into contact with over 100 embedded computer systems every day. A great many exist in our homes without our realizing it and many more operate the commonplace items in the world around us. An "embedded system" is a self contained miniaturized "computer system" (CPU, memory, I/O) that is dedicated to performing a single type of operation. They are now common in households through HVAC (Heat Ventilation and Air Conditioning), stoves, refrigerators, televisions, video players, set-top boxes, lawn sprinkler systems, and many other items. They are in the world around us controlling our street lighting, door openers, intruder alert systems, product theft security, speed cameras, and much more. The concept of security for these buses is traditionally very low because the designer has always been able to depend on physical security of an enclosed box. However, as more of the "boxes" are connected together more external buses and networks come into being and more opportunities for access and malfunction, whether through poor design, unforeseen circumstances, or foul play, become possible. This is a discussion of the progression of design from self-contained systems to more complex ones with internal buses and finally external standard buses. There will be an explanation of what an embedded system is and examples of complex embedded networks. Their security, and hence your security, is at risk in many cases, much of it due to "security through obscurity."