64-bit computing definition from wikipedia
: In computer architecture, 64-bit computing is the use of processors that have datapath widths, integer size, and memory addresses widths of 64 bits (eight octets).
Year 64 (LXIV) was a leap year starting on Sunday (link will display the full calendar) of the Julian calendar. At the time, it was known as the Year of the Consulship of Bassus and Crassus (or, less frequently, year 817 Ab urbe condita). The denomination 64 for this year has been used since the early medieval period, when the Anno Domini calendar era became the prevalent method in Europe for naming years.