Background
Douglas Carl Engelbart (January 30, 1925 – July 2, 2013) was an engineer and inventor, and an early computer and Internet pioneer. He is best known for his work on founding the field of human–computer interaction, particularly while at his Augmentation Research Center Lab in SRI International, which resulted in creation of the computer mouse, and the development of hypertext, networked computers, and precursors to graphical user interfaces. These were demonstrated at The Mother of All Demos 
in 1968. Engelbart's law , the observation that the intrinsic rate of human performance is exponential, is named after him. wikipedia
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