third generation computer

third generation computer

   <architecture> A computer built with small-scale integration
   {integrated circuits}, designed after the mid-1960s.

   Third generation computers use {semiconductor} memories in
   addition to, and later instead of, {ferrite core memory}.  The
   two main types of semiconductor memory are {Read-Only Memory}
   (ROM) and read-and-write memories called {random-access
   memory} (RAM).

   A technique called {microprogramming} became widespread and
   simplified the design of the {CPUs} and increased their
   flexibility.  This also made possible the development of
   {operating systems} as {software} rather than as hard-wiring.

   A variety of techniques for improving processing efficiency
   were invented, such as {pipelining}, (parallel operation of
   {functional units} processing a single instruction), and
   {multiprocessing} (concurrent execution of multiple programs).

   As the execution of a program requires that program to be in
   memory, the concurrent running of several programs requires
   that all programs be in memory simultaneously.  Thus the
   development of techniques for concurrent processing was
   matched by the development of {memory management} techniques
   such as {dynamic memory allocation}, {virtual memory}, and
   {paging}, as well as {compilers} producing {relocatable code}.

   The {LILLIAC IV} is an example of a third generation computer.

   The CTSS ({Compatible Time-Sharing System}) was developed at
   {MIT} in the early 1960s and had a considerable influence on
   the design of subsequent timesharing operating systems.

   An interesting contrasting development in this generation was
   the start of mass production of small low-cost
   "{minicomputers}".