The Hypertext Editing System, or HES, was an early

hypertext Hypertext is text displayed on a computer display or other electronic devices with references ( hyperlinks) to other text that the reader can immediately access. Hypertext documents are interconnected by hyperlinks, which are typicall ...

research project conducted at Brown University in 1967 by Andries van Dam, Ted Nelson, and several Brown students.Brown University Department of Computer Science. (23 May 2019)
A Half-Century of Hypertext at Brown
It was the first hypertext system available on commercial equipment that novices could use. HES organized data into two main types: links and branching text. The branching text could automatically be arranged into menus, and a point within a given area could also have an assigned name, called a label, and be accessed later by that name from the screen. Although HES pioneered many modern hypertext concepts, its emphasis was on text formatting and printing. HES required an IBM 2250 display console and a large memory partition on Brown's IBM System/360 Model 50 campus

mainframe computer A mainframe computer, informally called a mainframe or big iron, is a computer used primarily by large organizations for critical applications like bulk data processing for tasks such as censuses, industry and consumer statistics, enterpris ...

which limited its use: "Although it was shared with others, it was a multi-million-dollar piece of technology housed in a large machine room that van Dam’s team was able to use as essentially a personal computer between midnight and 4 AM." The program was used by

NASA The National Aeronautics and Space Administration (NASA ) is an independent agency of the US federal government responsible for the civil space program, aeronautics research, and space research. NASA was established in 1958, succeedi ...

's Houston Manned Spacecraft Center for documentation on the

Apollo Apollo, grc, Ἀπόλλωνος, Apóllōnos, label=genitive , ; , grc-dor, Ἀπέλλων, Apéllōn, ; grc, Ἀπείλων, Apeílōn, label=Arcadocypriot Greek, ; grc-aeo, Ἄπλουν, Áploun, la, Apollō, la, Apollinis, label= ...

space program. The project's research was funded by IBM but the program was stopped around 1969, and replaced by the FRESS (File Retrieval and Editing System) project. Ted Nelson claims credit for inventing the back button with regards to hypertext, as the Hypertext Editing System was the first system that contained one.

References

{{hypermedia Hypertext Brown University History of human–computer interaction