IBM recently celebrated the 50th anniversary of the System/360 mainframe, which was announced on April 7, 1964.
The System/360, or S/360 is discussed in this IBM video, “IBM Centennial Film: They Were There.”
Also from IBM, System 360: From Computers to Computer Systems:
Most significantly, the S/360 ushered in an era of computer compatibility—for the first time, allowing machines across a product line to work with each other. In fact, it marked a turning point in the emerging field of information science and the understanding of complex systems. After the S/360, we no longer talked about automating particular tasks with “computers.” Now, we talked about managing complex processes through “computer systems.”