AS A programmer, interface designer, writer and consultant, Jef Raskin devoted his working life to finding ways to make computers more usable. One of the earliest employees at Apple Computer in the late 1970s, he pushed the company to build an easy-to-use personal computer and led the Macintosh project in its early stages.

Although the computer that was launched in 1984 owed more to the ideas of Apple co-founder Steve Jobs than to Raskin’s original vision, he is generally regarded as the “father of the Macintosh”.

Born in New York in 1943, Jef Raskin demonstrated an early interest in rockets and model aeronautics, and an aptitude for mathematics and music. At college he designed and built computers for the biology department of the State University of New York, before becoming an undergraduate there in 1960. He took two bachelors degrees: one in mathematics and physics in 1964 and a second, in philosophy, in 1965. He also worked as a computer operator and programmer and pursued his hobby of making and flying model aircraft.

Although he began working towards a PhD in philosophy at Pennsylvania State University, he switched to computer science and in 1967 was awarded a masters degree for his thesis on hardware-independent computer graphics systems. At a time when most computers used simple text-only screen displays, his work looked forward to the days of graphical user interfaces.

Raskin then moved to La Jolla, California, and began postgraduate work in electronic and computer music at the University of California at San Diego. In 1969 he became a lecturer, dividing his time between the computing and visual arts faculties, before becoming an assistant professor in computing the following year.

In 1974 he moved to Brisbane, just south of San Francisco, and founded two companies. Bannister and Crum offered consulting and documentation services to the rapidly expanding computing industry in the newly emerging Silicon Valley, while Jef’s Friends Model Aircraft produced and sold radio-controlled model aerocraft in an unsuccessful attempt to turn a hobby into a profitable business.

Raskin met the Apple Computer founders Steve Wozniak and Steve Jobs in 1976, the year before they established the company, but just after they had completed the Apple I computer. Raskin’s company, Bannister and Crum, wrote documentation for the Apple I and its successor, the Apple II, and in 1978 he became employee No 31 at Apple, closing down both of his businesses shortly after.

Raskin was initially responsible for writing user guides and manuals, but in 1979 he began work on the design of a radical new computer which he called the Macintosh. It was to be cheap, aimed at consumers rather than computer professionals and be very easy to use.

The name came from his favourite variety of apple, the McIntosh, with the spelling changed to avoid trademark conflict with a music program of the time.

Although Raskin initiated the project to build the Macintosh, he did not see it through to its successful conclusion in 1984. In 1981 he was removed from the team after a dispute with Steve Jobs over the sort of computer to build, and in 1982 he left Apple. Raskin saw the Mac as a simple tool for specific tasks, an “information appliance”, but Jobs wanted a general-purpose computer.

The relationship between the two never recovered, and this led indirectly to the continuing confusion over the precise history of the Macintosh’s development as each side presented significantly different chronologies to reporters and chroniclers. However many of Raskin’s early ideas on interface and product design seem to have influenced the product team, and innovations such as “click and drag” (holding the mouse button down over an object and then moving it) came from him.

He also founded Information Appliance Inc., taking the name from the term he had coined to describe the sort of computer he wanted the Macintosh to be, one that put the user first and required no great technical skill to operate.

Raskin’s implementation of the information appliance was eventually taken on by Canon, who renamed it the Canon Cat. It was released in 1987 but was never a commercial success and was soon withdrawn from the market.

From 1989 he worked as an independent consultant and influenced the design of user interfaces through his writing, lectures and consulting work. In his book The Humane Interface (2000) he argued that existing ways of using computers are no longer acceptable and that it is time to develop new interfaces. He assembled a team to create “The Humane Environment”, a practical implementation of his principles, and established the Raskin Centre for Humane Interface.

Last December he told friends that he was suffering from pancreatic cancer; at the same time his new research centre received start-up funding of $2 million. His son, Aza, will continue to work as a programmer on the centre's latest project, named Archy.

Although best known as a computer scientist, Raskin was also an accomplished musician. In the 1970s he taught the recorder, harpsichord and music theory at San Francisco Community College and conducted the San Francisco Chamber Opera Society. He is also an expert on the aerodynamics of miniature aircraft and had a patent for aircraft wing construction. He is survived by his wife, Linda, and by a son and two daughters.

Jef Raskin, computer scientist, was born on March 9, 1943. He died on February 26, 2005, aged 61.