Editing IBM Future Systems project (section)

===AFS===
In 1969, [[Bob O. Evans]], president of the  IBM System Development Division which developed their largest [[mainframe]]s, asked [[Erich Bloch]] of the [[IBM Poughkeepsie Lab]] to consider how the company might use these much cheaper components to build machines that would still retain the company's profits. Bloch, in turn, asked [[Carl Conti]] to outline such systems. Having seen the term "future systems" being used, Evans referred to the group as Advanced Future Systems. The group met roughly biweekly.

Among the many developments initially studied under AFS, one concept stood out. At the time, the first systems with [[virtual memory]] (VM) were emerging, and the seminal [[Multics]] project had expanded on this concept as the basis for a [[single-level store]]. In this concept, all data in the system is treated as if it is in [[main memory]], and if the data is physically located on [[secondary storage]], the VM system automatically loads it into memory when a program calls for it. Instead of writing code to read and write data in files, the programmer simply told the operating system they would be using certain data, which then appeared as objects in the program's memory and could be manipulated like any other [[variable (computer science)|variable]]. The VM system would ensure that the data was synchronized with storage when needed.<ref name=hansen>{{cite magazine |first=Bill |last=Hansen |date=11 March 2019 |title=Fifty Years of Operating IBM Systems |magazine=The Four Hundred |volume=29 |issue=15 |url=https://www.itjungle.com/2019/03/11/fifty-years-of-operating-ibm-systems/}}</ref>

This was seen as a particularly useful concept at the time, as the emergence of [[bubble memory]] suggested that future systems would not have separate [[core memory]] and [[disk drive]]s, instead everything would be stored in a large amount of bubble memory.<ref name=hansen/> Physically, systems would be single-level stores, so the idea of having another layer for "files" which represented separate storage made no sense, and having pointers into a single large memory would not only mean one could simply refer to any data as it if were local, but also eliminate the need for separate [[application programming interface]]s (APIs) for the same data depending on whether it was loaded or not.<ref name=hansen/>