Memex is the name of the hypothetical electromechanical device that Vannevar Bush described in his 1945 article "As We May Think". Bush envisioned the memex as a device in which individuals would compress and store all of their books, records, and communications, "mechanized so that it may be consulted with exceeding speed and flexibility". The individual was supposed to use the memex as automatic personal filing system, making the memex "an enlarged intimate supplement to his memory".
The concept of the memex influenced the development of early hypertext systems, eventually leading to the creation of the World Wide Web, and personal knowledge base software. The hypothetical implementation depicted by Bush for the purpose of concrete illustration was based upon a document bookmark list of static microfilm pages and lacked a true hypertext system, where parts of pages would have internal structure beyond the common textual format.
In "As We May Think", Vannevar Bush describes a memex as an electromechanical device enabling individuals to develop and read a large self-contained research library, create and follow associative trails of links and personal annotations, and recall these trails at any time to share them with other researchers. This device would closely mimic the associative processes of the human mind, but it would be gifted with permanent recollection. As Bush writes, "Thus science may implement the ways in which man produces, stores, and consults the record of the race".