Vannevar Bush

In his essay, "As We May Think", Bush talk about a theoretical machine called a "memex" that enhances human memory by allowing the user to store and retrieve documents linked by associations. This was very similar to what's known today as hypertext.
Many, such as Ted Nelson and Douglas Engelbart, were inflenced by his idea.

Ted Nelson

He is known for coining the term "hypertext". This was very similar to that envisioned by Vannevar Bush. Also, his biggest project, Xanadu, was to be a world-wide electronic publishing system that would have created a sort universal libary for the people.

Doug Engelbart

His famous invention is the computer mouse. Like Vannevar Bush, Engelbart wanted to use technology to augment human intellect.