Abstract: Since its introduction decades ago, x-ray computed tomography (CT) has revolutionized radiographic imaging and generated major healthcare benefits. Closely correlated to the development of x-ray CT, increasingly higher data acquistion speed has been intensively pursued for better studies on dynamic processes such as cardiac diseases.  Our group has made signficant contributions in this main stream direciton, including spiral/helical CT, multi-source design, and so on.  Most recently, we invented interior tomography and are actively evaluting its implications for ultrafast (even instant) tomography. In this talk, from the temporal resolution perspective we overview the CT field and look into the future.