The Solid Logic Technology by IBM was the first step to "circuits" in computers. So the whole concept of computers changed basically on April the 7th in 1964. This technology was published with the System/360. It was a hybrid technology with transistor-modules and other devices on a circuit board. SLT was a revolutionary technology for the year 1964 with improvements compared to other manufacturing technologies and brought an enormous success to the IBM/360-mainframes during the 1960s. IBM produced hundred-million of SLT-modules in a highly automated, special built manufacturing plant in East Fishkill, NY.