Converged infrastructure operates by grouping multiple information technology (IT) components into a single, optimized computing package. Components of a converged infrastructure may include servers, data storage devices, networking equipment and software for IT infrastructure management, automation and orchestration.
for more information you can go on: http://en.wikipedia.org/wiki/Converged_infrastructure
HP came up with the name a few years ago to describe their system of combining storage, networking and computational tools into a single resource pool. Other companies have different names for what is essentially the same thing, for example, Cisco calls it the unified computing system. It's not really vendor spin, but it is a marketing driven name for something other companies offer as well.