 Measurement-based algorithms differ from circuit algorithms in that instead of employing unitary evolution as the basic mechanism for the manipulation of information, these algorithms essentially make use of non-unitary measurements in the course of a computation. They are especially interesting from a foundational perspective because they have no evident classical analogues and because they offer new insight on the role of  entanglement  in quantum computing (Jozsa 2006). They may also have interesting engineering-related consequences, suggesting a different kind of computer architecture which is more fault tolerant (Nielsen and Dawson 2005).