Larry (formally Lawrence Gordon) Tesler (born April 24, 1945) is a computer scientist working in the field of human-computer interaction. Tesler has worked at Xerox PARC, Apple Computer, Amazon.com, and Yahoo!
Tesler studied computer science at Stanford University in the 1960s, and worked for a time at the Stanford Artificial Intelligence Laboratory. From 1973 to 1980, he was at Xerox PARC, where, among other things, he worked on the Gypsy word processor and Smalltalk.
In 1980, Tesler moved to Apple Computer, where he held various positions, including Vice President of AppleNet, Vice President of the Advanced Technology Group, and Chief Scientist.[1] He worked on the Apple Lisa team and was enthusiastic about the development of the Macintosh as well as the successors to the Lisa the Apple II series and Lisa's later high end replacement the Macintosh Plus.
In 1985, Tesler worked with Niklaus Wirth to add object-oriented language extensions to the Pascal programming language, calling the new language Object Pascal. He also was instrumental in developing MacApp, one of the first class libraries for application development. Eventually, these two technologies became shipping Apple products.
Starting in 1990, Tesler led the efforts to develop the Apple Newton, initially as Vice President of the Advanced Development Group, and then as Vice President of the Personal Interactive Electronics division.
In 1991, he contributed the article "Networked Computing in the 1990s" to Scientific American Special Issue on Communications, Computers, and Networks, September, 1991.
Tesler left Apple in 1997 to co-found Stagecast Software, which allowed him to apply his enthusiasm for kids' programming and use of computers, an enthusiasm he acquired mainly at Xerox PARC, where he worked in Alan Kay's Learning Research Group.
Tesler joined Amazon.com in 2001; in 2004, he became the company's Vice President of Shopping Experience. In 2005, he joined Yahoo! as Vice President of Yahoo!'s User Experience and Design group.[2]
In November, 2008, he left Yahoo to join personal genetics information company, 23andMe as Product Fellow. Since December, 2009, he has been an independent consultant.
Tesler is on the board of the Gorilla Foundation.
Tesler has a strong preference for modeless software, in which a user action has a consistent effect, rather than changing its meaning dependent on previous actions, as in the vi text editor . His Gypsy editor, for example, provided a 'click and type' interface in which the user could, at any time, enter text at the current insertion point, or click where the insertion point should be repositioned. Previously, most editors used the keyboard to enter text or to issue commands, depending on the current mode. To promote his preference, as of 2010, Tesler has equipped his Subaru automobile with a personalized California license plate with the license number "NO MODES". He has used this license number since about 1980. Along with others, he has also been using the phrase "Don't Mode Me In" for years as a rally cry to eliminate or reduce modes.[3]