What familiar device was invented by human-computer interface engineer Douglas Engelbart, creator of hypertext?
Purple Numbers Purple Numbers is a suite of tools that allows one to address paragraphs of HTML content. It was originally conceived by Douglas Engelbart for his creation of hypertext. The name comes from the faint, purple numbers at the end of each paragraph, which represent the link to that paragraph. The name was coined by Christina Engelbart, Doug's daughter.
DiamondTouch The DiamondTouch table is a multi-touch, interactive PC interface product from Circle Twelve Inc. It is a human interface device that has the capability of allowing multiple people to interact simultaneously while identifying which person is touching where. The technology was originally developed at Mitsubishi Electric Research Laboratories (MERL) in 2001 and later licensed to Circle Twelve Inc in 2008. The DiamondTouch table is used to facilitate face-to-face collaboration, brainstorming, and decision-making, and users include construction management company Parsons Brinckerhoff, the Methodist Hospital, and the US National Geospatial-Intelligence Agency (NGA).