By providing the ability to host multiple systems on a single physical machine,
virtualization helps organizations increase equipment utilization rates, conserving data
center space and energy usage. Most servers run at just 15-20 percent of capacity, and vir-
tualization can boost server utilization rates to 70 percent or higher. Higher utilization rates
translate into fewer computers required to process the same amount of work, as illustrated
by BART's experietfce with virtualization in the chapter-opening case. Virtualization also
facilitates centralization and consolidation of hardware administration. It is now possible
for companies and individuals to perform all of their computing work using a virtualized lT
infrastructure, as is the case with cloud computing.