Don Norman is the co Founder and consultant of the Nielsen Norman Group. He is best known for his book ‘The  Design of Everyday Things’. He has expertise in design, usability, and cognitive science. Norman’s work always gave importance to user-centered design. He always served the purpose of improving the design of all the things which people come across in the daily life. He has been encouraging for creativity and technological innovation to refine existing products. 

According to Don, the main goal of designing has always been to make things simpler to use, see, feel & understand. He believed that products or websites should not be limited to just the user experience, but the entire interaction it has with the end user. 

Jakob Nielsen is the User Advocate and principle of the Nielsen Norman Group which he co founded with Don Norman. Nielsen is a web usability consultant by profession. He founded the “Discount Usability Engineering” movement for fast and cheap movements of user interfaces and has invented several usability methods including heuristics evaluations. He writes a fortnightly newsletter ‘Alertbox’ on web design matters. Nielsen defined the five quality components of his ‘Usability Goals’ which are Learnability, Efficiency, Memorability, Error and Satisfaction. 

Cooper is recognised as the ‘Father of Visual BASIC’. He is the Co founder of the design firm Cooper. 

In 1988, Alan Cooper invented the visual basic programme “Ruby”, and demonstrated to Bill Gates, who purchased it and combined it with QUICKBASIC to create VISUAL BASIC. 

Cooper created the goal-directed design methods (focus was shifted from what a product can do to what it can do for its users) that is being used across the industry and also invented design personas as practical design interaction tool.