I have been working more than 44 years in the IT industry.  As would be expected my first experiences and the majority of my working years was with machines now called mainframes.  The latter is associated with large machines (physically) and small memories.   After 30 years I thought, as many others did, that we have reached an end of an era and that the writing is on the wall for the so-called mainframes.  However it turns out that mainframes are not dead, in fact they are becoming a force to be reckoned with.  With specific reference to the IBM System Z, these machines may be called mainframes but are no larger than your typical Unix type servers.  Their performance in an OLTP environment is outstanding – banks, airline reservation systems is proof thereof.  This is the architecture where the acronym RAS was coined – Reliability, Availability and Serviceability.   The latter not only with respect to the hardware but even more so the operating systems such as zOS.  As in the case of the hardware architecture the operating system has evolved over a period of 45 years.  As a result there is now an academic interest in the mainframe and courses are available at most universities on the IBM mainframe architecture and software.  The latter is a requirement in the USA and Europe in order to train more youngsters (under 30) in this field as there is a skills shortage.  In my own experience this also applies to South Africa where we unfortunately also had to deal with the so-called brain-drain.  As us older folks depart to greener pastures there is the potential for a real vacuum as far as “mainframe” skills are concerned in South Africa and I think companies that are dependent on mainframe skills should seriously invest in training new “techies” in this challenging field.  This is not a case of wishful thinking as I believe that the mainframe is coming back with a vengeance.  I would put more faith when some of our service providers get rid of their farms of blade servers etc and replace them with a single mainframe computer.  And if they so wish run multiple instances of Linux on those mainframes.