delphi (later known as delphi 1) was released in 1995 for the 16-bit windows 3.1, and was an early example of what became known as rapid application development (rad) tools. delphi evolved from borland's "turbo pascal for windows", itself an evolution with windows support from borland's turbo pascal and borland pascal with objects, very fast 16-bit native-code ms-dos compilers with their own sophisticated integrated development environment (ide) and textual user interface toolkit for dos (turbo vision). early turbo pascal (for ms-dos) was written in a dialect of the pascal programming language; in later versions support for objects was added, and it was named object pascal. delphi has always used object pascal, which continued to be developed, as its underlying object-oriented language.