Anders Hejlsberg is a Danish software engineer best known as the original author of Turbo Pascal, and later as the chief designer of several major programming languages. Microsoft, where he became a Technical Fellow, describes him as “an influential creator of development tools and programming languages,” “the original author of Turbo Pascal, a revolutionary integrated development environment, and chief architect of its successor, Delphi,” and “the chief designer of the C# programming language.”
According to that same Microsoft biography, Hejlsberg “studied engineering at the Technical University of Denmark.” Widely repeated accounts add that he attended the university but left without completing a degree; that specific detail is not stated in the firsthand Microsoft source cited here, so it should be treated with some caution. What is well documented is that the work he is famous for began outside any classroom, with a fast and compact Pascal compiler he wrote himself.
That compiler became Turbo Pascal when the young company Borland began selling it in 1983. Its defining feature was speed and integration: editor, compiler, and run environment combined in a single small program that compiled directly in memory, at a time when most compilers were slow, expensive, and required swapping to disk. The Turbo Pascal Reference Manual describes the product as offering “compilation and execution times second to none.”
After Turbo Pascal and Delphi, Hejlsberg joined Microsoft in 1996 and went on to design C#, and later to lead the creation of TypeScript, a typed layer on top of JavaScript. For the Code Library he is the anchor figure of the Pascal story: one engineer’s compiler turned a teaching language into a tool that put professional development on hobbyist machines.