We have had multi-core processors in our PCs for over a decade, and today they are considered the norm. At first it was dual-core, then quad-core, and today companies like Intel and AMD offer high end desktop processors with 6 or even 8 cores. Smartphone processors have a similar history. Dual-core energy efficient processors from ARM arrived about 5 years ago, and since then we have seen the release of ARM based 4, 6 and 8 core processors. However there is one big difference between the 6 and 8 core desktop processors from Intel and AMD and the 6, and 8 core processors based on the ARM architecture – most ARM based processors with more than 4 cores use at least two different core designs.