Lawrence Gordon Tesler (born April 24, 1945) is a computer scientist who works in the field of human–computer interaction. Tesler has worked at Xerox PARC, Apple, Amazon, and Yahoo!. Tesler has a strong preference for modeless software, in which a user's action has a consistent effect, rather than changing its meaning depending 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 equipped his Subaru automobile with a personalized California license plate with the license number "NO MODES". 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.
1 Biography 2 See also 3 References 4 External links
Tesler grew up in New York City and graduated from the Bronx High
School of Science in 1961. He went on to Stanford University, where he
studied computer science in the 1960s, and worked for a time at the
Stanford Artificial Intelligence Laboratory. With Horace Enea, he
designed Compel, an early single assignment language. This functional
programming language was intended to make concurrent processing more
natural and was used to introduce programming concepts to
In the late 1960s, Tesler became involved in the Midpeninsula Free
University, where he delivered classes about topics such as How to end
the IBM Monopoly, Computers Now, and Procrastination.
In the 1970s, from 1973 to 1980, Tesler worked at Xerox PARC, where
some of his main projects were the Gypsy word processor and Smalltalk.
Copy and paste was first implemented in 1973-1976 by Tesler and Tim
Mott, while they were working on Gypsy for Xerox Palo Alto Research
In 1980, Tesler moved to Apple Computer, holding various positions
including Vice President of AppleNet, Vice President of the Advanced
Technology Group, and Chief Scientist. He worked on the Lisa
team, and was enthusiastic about the development of the Macintosh as
the successor to the Lisa.
In 1985, Tesler worked with
Wikimedia Commons has media related to Larry Tesler.
AI effect List of programmers List of computer scientists Law of conservation of complexity
^ "vi, command and input modes". rcsg-gsir.imsb-dsgi.nrc-cnrc.gc.ca.
^ a b Tesler, Larry (1981). "The
1999 Lecture on Novice Programming
Founders 1999 Lecture on Novice