'''IBM System/360''' (and '''IBM System/370''')

The architecturally compatible line of MainframeComputer''''''s whose success, following huge financial risk, allowed IBM (InternationalBusinessMachines) to dominate the BigIron business in the 1960s and 1970s. The whole project was led by FredBrooks; GeneAmdahl was the chief architect for the hardware.

Its logo was a compass rose, signifying the 360 degrees - the full circle - of computing applications that could be addressed with the System/360 architecture, replacing the previously customarily separate lines of commercially oriented MainframeComputer''''''s versus scientifically oriented SuperComputer''''''s. ''Also the full software-compatiblity across (almost) the entire price range of 360 models, another "first" and one of the line's central achievements.''

Brooks decided that it would adopt EbcdicCode, an 8-bit character set including lower-case letters, another significant milestone for the time.

Its instruction set was summarized on a folding quick reference printed on mint-green 
card stock, thus coming to be known throughout much of the computer industry as the ''Green Card''.  The instruction set of its successor ''System/370'' architecture, whose fully developed models were characterized by ''virtual memory'' and ''cache'' features,
was printed on yellow or light-goldenrod card stock, and quickly dubbed the ''Yellow Card''.

While the hardware was considered a great success, the project to create the system software became a bellwether of the SoftwareCrisis. ''MythicalManMonth'' was mostly based on FredBrooks' experience as head of the project.

* Promo photo of 360: http://www.lileks.com/institute/compupromo/4.html
* Promo photo of 370: http://www.lileks.com/institute/compupromo/6.html

----
CategoryMainframeComputing CategoryHardware CategoryComputerArchitecture